Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.1

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Maths Guide Pdf Chapter 11 Integral Calculus Ex 11.1 Text Book Back Questions and Answers, Notes.

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Integrate the following with respect to x:

Question 1.
(i) x11
(ii) \(\frac{1}{x^{7}}\)
(iii) \(\sqrt[3]{x^{4}}\)
(iv) (x5)1/8
Answer:
(i) x11
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.1 1

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.1

(ii) \(\frac{1}{x^{7}}\)
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.1 2

(iii) \(\sqrt[3]{x^{4}}\)
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.1 3

(iv) (x5)1/8
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.1 4

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.1

Question 2.
(i) \(\frac{1}{\sin ^{2} x}\)
(ii) \(\frac{\tan x}{\cos x}\)
(iii) \(\frac{\cos x}{\sin ^{2} x}\)
(iv) \(\frac{1}{\cos ^{2} x}\)
Answer:
(i) \(\frac{1}{\sin ^{2} x}\)
\(\frac{1}{\sin ^{2} x}\) = ∫cosec2 x dx
= – cot x + c

(ii) \(\frac{\tan x}{\cos x}\)
\(\frac{\tan x}{\cos x}\) = ∫sec x tan x dx
= sec x + c

(iii) \(\frac{\cos x}{\sin ^{2} x}\)
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.1 5

(iv) \(\frac{1}{\cos ^{2} x}\)
\(\frac{1}{\cos ^{2} x}\) = ∫sec2 x dx
= tan x + c

Question 3.
(i) 123
(ii) \(\frac{x^{24}}{x^{25}}\)
(iii) ex
Answer:
(i) 123
∫123 dx = 123 ∫dx = 123x + c

(ii) \(\frac{x^{24}}{x^{25}}\)
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.1 6

(iii) ex
∫ex dx = ex + c

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.1

Question 4.
(i) (1 + x2)-1
(ii) (1 – x2)-1/2
Answer:
(i) (1 + x2)-1
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.1 7

(ii) (1 – x2)-1/2
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.1 8

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Maths Guide Pdf Chapter 11 Integral Calculus Ex 11.2 Text Book Back Questions and Answers, Notes.

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Integrate the following functions with respect to x

Question 1.
(i) (x + 5)6
(ii) \(\frac{1}{(2-3 x)^{4}}\)
(iii) \(\sqrt{3 x+2}\)
Answer:
(i) (x + 5)6
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2 1

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2

(ii) \(\frac{1}{(2-3 x)^{4}}\)
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2 2

(iii) \(\sqrt{3 x+2}\)
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2 3

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2

Question 2.
(i) sin 3x
(ii) cos (5 – 11x)
(iii) cosec2 (5x – 7)
Answer:
(i) sin 3x
∫sin (ax + b) dx = – \(\frac{1}{a}\) cos (ax + b) + c
∫sin 3x dx = – \(\frac{1}{3}\) cos 3x + c

(ii) cos (5 – 11x)
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2 4

(iii) cosec2 (5x – 7)
[∫cosec2 (ax + b) dx = – \(\frac{1}{a}\) cot (ax + b) + c]
∫cosec2 (5x – 7) dx = – \(\frac{1}{5}\) cot (5x – 7) + c

Question 3.
(i) e3x – 6
(ii) e8 – 7x
(iii) \(\frac{1}{6-4 x}\)
Answer:
(i) e3x – 6
[∫eax+b dx = \(\frac{1}{a}\) eax + b + c]
∫e3x – 6 dx = \(\frac{1}{3}\) e3x – 6 + c

(ii) e8 – 7x
[∫eax+b dx = \(\frac{1}{a}\) eax + b + c]
∫e8 – 7x = \(\frac{1}{-7}\) e8 – 7x + c
∫e8 – 7x = \(-\frac{1}{7}\) e8 – 7x + c

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2

(iii) \(\frac{1}{6-4 x}\)
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2 5

Question 4.
(i) sec2 \(\frac{x}{5}\)
(ii) cosec (5x + 3) cot (5x + 3)
(iii) 30 sec (2 – 15x) tan (2 – 15x)
Answer:
(i) sec2 \(\frac{x}{5}\)
[∫sec2 (ax + b)dx = \(\frac{1}{a}\) tan (ax + b) + c]
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2 6

(ii) cosec (5x + 3) cot (5x + 3)
[∫cosec (ax + b) cot (ax + b) dx = – \(\frac{1}{a}\) cosec (ax + b) + c]
∫cosec (5x + 3) cot (5x + 3) dx = – \(\frac{1}{5}\) cosec (5x + 3) + c]

(iii) 30 sec (2 – 15x) tan (2 – 15x)
[∫sec (ax + b) tan (ax + b)dx = \(\frac{1}{a}\) sec (ax + b) + c]
∫30 sec (2 – 15x) tan (2 – 15x)dx = 30 × \(\frac{1}{-15}\) × sec (2 – 15x) + c
= – 2 sec (2 – 15x) + c

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2

Question 5.
(i) \(\frac{1}{\sqrt{1-(4 x)^{2}}}\)
(ii) \(\frac{1}{\sqrt{1-81 x^{2}}}\)
(iii) \(\frac{1}{1+36 x^{2}}\)
Answer:
(i) \(\frac{1}{\sqrt{1-(4 x)^{2}}}\)
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2 7

(ii) \(\frac{1}{\sqrt{1-81 x^{2}}}\)
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2 8

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2

(iii) \(\frac{1}{1+36 x^{2}}\)
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.2 9

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Maths Guide Pdf Chapter 11 Integral Calculus Ex 11.3 Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Maths Solutions Chapter 11 Integral Calculus Ex 11.3

Integrate the following with respect to x:

Question 1.
(x + 4)5 + \(\) – cosec2 (3x – 1)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3 1
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3 2

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3

Question 2.
4 cos (5 – 2x) + 9 e3x – 6 + \(\frac{24}{6-4 x}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3 3

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3

Question 3.
sec2 \(\frac{x}{5}\) + 18 cos 2x + 10 sec (5x + 3) tan (5x + 3)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3 4

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3

Question 4.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3 5
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3 6
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3 7

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3

Question 5.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3 8
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3 9

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3

Question 6.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3 10
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3 11
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.3 12

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.4

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Maths Guide Pdf Chapter 11 Integral Calculus Ex 11.4 Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Maths Solutions Chapter 11 Integral Calculus Ex 11.4

Question 1.
If f'(x) = 4x – 5 and f(2) = 1, find f(x)
Answer:
\(\int f^{\prime}(x) d x=\int(4 x-5) d x\)
f(x) = \(\frac{4 x^{2}}{2}\) – 5x + c
f(x) = 2x2 – 5x + c
But f(2) = 1
2(2)2 – 5(2) + c = 1
8 – 10 + c = 1
c = 3
Thus, f(x) = 2x2 – 5x + 3

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.4

Question 2.
If f'(x) = 9x2 – 6x and f(0) = – 3 find f(x).
Answer:
Given f’ (x) = 9x2 – 6x and f(0) = – 3
\(\frac{\mathrm{d} f(x)}{\mathrm{d} x}\) = 9x2 – 6x
df(x) = (9x2 – 6x) dx
∫ df(x) = ∫ (9x2 – 6x)
∫ df(x) = ∫ 9x2 dx – ∫ 6x dx
f(x) = 9 ∫x2 dx – 6 ∫ x dx
f(x) = 9 × \(\frac{x^{3}}{3}\) – 6 \(\frac{x^{2}}{2}\) + C
f(x) = 3x3 – 3x2 + c —— (1)
f(o) = – 3
(1) ⇒ f(0) = 3 × – 3 . 02 + c
– 3 = 0 – 0 ⇒c = – 3
Substituting in equation (1) we get
f(x) = 3x3 – 3x2 – 3
f(x) = 3(x3 – x2 – 1)

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.4

Question 3.
If f” (x) = 12x – 6 and f(1) = 30, f’ (1) = 5, find f(x)
Answer:
\(\)
f'(x) = \(\) – 6x + c
f'(x) = 6x2 – 6x + c
But f'(1) = 5
6(1)2 – 6(1) + c = 5
c = 5
f” (x) = 6x2 – 6x + 5
\(\int f^{\prime \prime}(x) d x=\int\left(6 x^{2}-6 x+5\right) d x\)
f(x) = \(\frac{6 x^{3}}{3}-\frac{6 x^{2}}{2}\) + 5x + c
f(x) = 2x3 – 3x2 + 5x + c
But f(1) = 30
2(1)3 – 3(1)2 + 5(1) + c = 30
2 – 3 + 5 + c = 30
c = 26
f(x) = 2x3 – 3x2 + 5x + 26

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.4

Question 4.
A ball is thrown vertically upward from the ground with an initial velocity of 39.2 m / sec. If the only force considered is that attributed to the acceleration due to gravity, find
(i) how long will it take for the ball to strike the ground?
(ii) the speed with which will it strike the ground? and
(iii) how high the ball will rise?
Answer:
Initial velocity of the ball = 39.2 in / s
Let s be the distance of the ball from the ground at time t.
u = 39.2m/s.
s = ut – \(\frac{1}{2}\) . gt2 where g = 9.8 m / sec.
s = 39.2 t – \(\frac{1}{2}\) × (9.8) t2
s = 39.2 t – 49 t2

(i) how long will it take for the ball to strike the ground?
For the ball to strike the ground, s = 0
∴ 39.2 t – 4.9 t2 = 0
t(39.2 – 4.9 t) = 0
39.2 – 4.9 t = 0 since t ≠ 0
4.9 t = 39.2
t = \(\frac{39.2}{4.9}\) = 8
t = 8 sec.

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.4

(ii) The speed with which will it strike the ground?
At t = 8; (1) ⇒ v = -9.8(8) + 39.2
= -78.4 + 39.2
= -39.2
∴ The speed with which the ball will strike the ground is = 39.2 m/s
(iii) At maximum height v = 0
⇒ (2) ⇒ -9.8 t + 39.2 = 0
t = 4 sec
⇒ (3) ⇒ x = \(-\frac{9.8 \times 16}{2}\) + 39.2 × 4
= -78.4 + 156.8 = 78.4 m/s

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.4

Question 5.
A wound is healing in such a way that t days since Sunday the area of the of the wound has been decreasing at a rate of \(-\frac{3}{(t+2)^{2}}\) cm2 per day. If on Monday the area of the wound was 2 cm2
(i) What was the area of the wound on Sunday?
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.4 1

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.4

(ii) What is the anticipated area of the wound on Thursday if it continues to heal at the same rate?
Answer:
(ii) From Sunday to Thursday there are 4 days. Substituting t = 4 in equation (2) we get
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.4 2
∴ The anticipated area of the wound on Thursday = 1.5 sq. cm.

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Maths Guide Pdf Chapter 11 Integral Calculus Ex 11.5 Text Book Back Questions and Answers, Notes.

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Integrate the following functions with respect to x

Question 1.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 1
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 2
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 3

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Question 2.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 4
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 5

Question 3.
(2x – 5) (3x + 4x)
Answer:
∫(2x – 5) (3x + 4x) dx
= ∫(72 x + 8x2 – 180 – 20x) dx
= ∫ 72 x dx + ∫82x2 dx – ∫180 dx – ∫2o x dx
= 72∫x dx + 8∫x2dx – 180 ∫dx – 20 ∫x dx
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 6

Question 4.
cot2 x + tan2 x
Answer:
∫cot2 x + tan2 x
= ∫(cosec2x – 1 + sec2x – 1) dx
= ∫(cosec2x + sec2x – 2) dx
= ∫cosec2x dx + ∫sec2x dx – ∫2 dx
= – cot x + tan x – 2x + c
= tan x – cot x – 2x + c

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Question 5.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 7
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 8
[cos 2x = cos2x – sin2x-1
cos 2x = 2 cos2x – 1]
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 9
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 10
= 2 ∫(cos x + cos α) dx
= 2 ∫ cos x dx + 2 ∫ cos α dx
= 2 ∫ cos x dx + 2 ∫ cos α ∫ dx
= 2 sin x + 2 cos α(x) + c
= 2 sin x + 2x cos α + c

Question 6.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 11
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 12
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 13

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Question 7.
\(\frac{3+4 \cos x}{\sin ^{2} x}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 14
= 3 ∫ cosec2 x dx + 4 ∫ cot x cosec x . dx
= 3 ∫ cosec2 x dx + 4 ∫ cosec x cot x dx
= 3 × – cot x + 4 × – cosec x + c
= – 3 cot x – 4 cosec x + c

Question 8.
\(\frac{\sin ^{2} x}{1+\cos x}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 15
= ∫ (1 – cos x) dx
= ∫ dx – ∫ cos x dx
= x – sin x + cannot

Question 9.
\(\frac{\sin 4 x}{\sin x}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 16
[sin 2A = 2 sin A cos A]
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 17
= 4 ∫ cos 2x cos x . dx
= 2 ∫ 2 cos 2x cosx . dx
= 2 ∫ [cos(2x + x) + cos(2x – x)] dx
[2 cos A cos B = cos (A + B) + cos (A – B)]
= 2 ∫ (cos 3x + cos x) dx
= 2 ∫ cos 3x dx + 2 ∫ cos x dx
= 2 \(\frac{\sin 3 x}{3}\) + 2 sin x + c
= 2 [\(\frac{\sin 3 x}{3}\) + sin x] + c

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Question 10.
cos 3x cos 2x
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 18

Question 11.
sin2 5x
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 19

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Question 12.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 20
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 21
[sin 2A = 2 sin A cos A]
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 22

Question 13.
ex log a ex
Answer:
∫ex log a ex = ∫e log ax . ex . dx
= ∫ ax ex . dx
= ∫ (ae)x . dx
[∫ax . dx = \(\frac{\mathrm{a}^{x}}{\log \mathrm{a}}\) + c]
= \(\frac{(\mathrm{ae})^{x}}{\log (\mathrm{ae})}\) + c

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Question 14.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 23
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 24
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 25

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Question 15.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 26
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 27
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 28

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Question 16.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 29
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 30
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 31

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Question 17.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 32
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 33
Put x = – 3
– 3 + 1 = A (- 3 + 3) + B (- 3 + 2)
– 2 = A × 0 + B (- 1)
B = 2

Put x = – 2
– 2 + 1 = A(- 2 + 3) + B(- 2 + 2)
– 1 = A × 1 + B × 0
A = – 1
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 34
= – log |x + 2| + 2 log |x + 3| + c
= 2 log |x + 3| – log |x + 2|+ c

Question 18.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 35
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 36
1 = A(x + 2)2 + B (x – 1) (x + 2) + C (x – 1)

Put x= -2
1 = A(- 2 + 2)2 + B(- 2 – 1) (- 2 + 2) + C(- 2 – 1)
1 = A × 0 + B × 0 + C × – 3
C = \(\frac{1}{3}\)

Put x = 1
1 = A(1 + 2)2 + B (1 – 1) (1 + 2) + C(1 – 1)
1 = A × 32 + B × 0 + C × 0
A = \(\frac{1}{9}\)

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Put x = 0
1 = A (0 + 2)2 + B (0 – 1) (0 + 2) + C (0 – 1)
1 = A × 4 – 2B – C
1 = \(\frac{1}{9}\) × 4 – 2B + \(\frac{1}{3}\)
1 = \(\frac{4}{9}+\frac{1}{3}\) – 2BSamacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 37
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 38

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Question 19.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 39
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 40
3x – 9 = A(x + 2) (x2 + 1) + B(x – 1) (x2 + 1) + (Cx + D) (x – 1) (x + 2)
3x – 9 = A (x + 2) (x2 + 1) + B(x – 1) + (x2 + 1) + Cx (x – 1) (x + 2) + D (x – 1) (x + 2)

Put x = – 2
3 × – 2 – 9 = A (- 2 + 2) ((2)2 + 1) + B(- 2 – 1) ((- 2)2 + 1) + C(- 2) (- 2 – 1) (- 2 + 2) + D(- 2 – 1) (- 2 + 2)
– 6 – 9 = A × 0 + B × (-3) (4 + 1) + C × 0 + D × 0
-15 = B ×- 3 × 5
-15 = – 15B ⇒ B = 1

Put x = 1
3 × 1 – 9 = A(1 + 2) (12 + 1) + B(1 – 1) (12 + 1) + C × 1 (1 – 1) (1 + 2) + D(1 – 1) (1 + 2)
3 – 9 = A × 3 × 2 + B × 0 + C × 0 + D × 0
– 6 = 6A ⇒ A = – 1

Put x = 0
3 × 0 – 9 = A(0 + 2) (02 + 1) + B(0 – 1) (02 + 1) + C × 0 (0 – 1) (0 + 2) + D(0 – 1) (0 + 2)
– 9 = 2A – B + 0 – 2D
– 9 = 2A – B – 2D
– 9 = – 2 × – 1 – 1 – 2D
– 9 = – 2 – 1 – 2D
9 = 3 + 2D
⇒ 2D = 9 – 3
⇒ 2D = 6 ⇒ D = 3

Put x = – 1
3 × – 1 – 9 = A(- 1 + 2) ((1)2 + 1) + B(- 1 – 1) ((- 1)2 + 1)) + C × – 1 × (- 1 – 1) (- 1 + 2) + D(- 1 – 1) (- 1 + 2)
– 3 – 9 = A × 1(1 + 1)+ B × (- 2) (1 + 1) – C × – 2 + D × – 2 × 1
– 12 = 2A – 4B + 2C – 2D
– 12 = 2 × -1 – 4 × 1 + 2C – 2 × 3
– 12 = – 2 – 4 + 2C – 6
– 12 = – 12 + 2C ⇒ C = 0
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 41
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 42

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Question 20.
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 43
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 44
Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 45
1 = A(x – 2) + B(x – 1)

put x = 2
1 = A(2 – 2) + B(2 – 1)
1 = A × 0 + B × 1
B = 1

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5

Put x = 1
1 = A(1 – 2) + B(1 – 1)
1 = A × – 1 + B × 0
A = – 1

Samacheer Kalvi 11th Maths Guide Chapter 11 Integral Calculus Ex 11.5 46

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Maths Guide Pdf Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Maths Solutions Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Find the derivatives of the following:

Question 1.
y = xcos x
Answer:
y = xcos x
Taking log on both sides
log y = log xcos x
log y = cos x log x
Differentiating with respect to x
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 1

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 2.
y = xlog x + (log x)x
Answer:
y = xlog x + (log x)x
Let u = xlog x, v = (log x)x
log u = log xlog x
log u = (log x) (log x)
log u = (log x)2
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 2
v = (log x)x
log v = log (log x)x
log v = x log (log x)
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 3

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 3.
\(\sqrt{x y}\) = e(x – y)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 4

Question 4.
xy = yx
Answer:
xy = yx
Taking log on both sides
log xy = log yx
y log x = x log y
Differentiate with respect to x
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 5

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 5.
(cos x)log x
Answer:
y = (cos x)log x
Taking log on both sides
log y = log (cos x)log x
log y = (log x) log (cos x)
Differentiating with respect to x
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 6

Question 6.
\(\frac{x^{2}}{a^{2}}+\frac{y^{2}}{b^{2}}=1\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 7

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 7.
\(\sqrt{x^{2}+y^{2}}=\tan ^{-1}\left(\frac{y}{x}\right)\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 8
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 9
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 10

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 8.
tan (x + y) + tan (x – y) = x
Answer:
tan (x + y) + tan (x – y) = x
Differentiating with respect to x
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 11

Question 9.
If cos(xy) = x, show that
\(\frac{d y}{d x}=\frac{-(1+y \sin (x y))}{x \sin x y}\)
Answer:
cos (xy) = x
Differentiating with respect to x
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 12

Question 10.
\(\tan ^{-1} \sqrt{\frac{1-\cos x}{1+\cos x}}\)
Answer:
Let y = \(\tan ^{-1} \sqrt{\frac{1-\cos x}{1+\cos x}}\)
[1 – cos 2θ = 2 sin2θ and 1 + cos 2θ = 2 sin2 θ]
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 13
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 14

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 11.
tan-1 = \(\left(\frac{6 x}{1-9 x^{2}}\right)\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 15
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 16

Question 12.
\(\cos \left(2 \tan ^{-1} \sqrt{\frac{1-x}{1+x}}\right)\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 17
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 18

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 13.
x = a cost ; y = a sin3t
Answer:
x = a cost , y = a sin3t
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 19

Question 14.
x = a (cos t + t sin t);
y = a (sin t – t cos t)
Answer:
x = a (cos t + t sin t) , y = a (sin t – t cos t)
\(\frac{d x}{d t}\) = a [- sin t + t cos t + sin t ]
\(\frac{d x}{d t}\) = at cos t —— (1)
y = a (sin t – t cos t)
\(\frac{d x}{d t}\) = a [cos t – (t × – sin t + cos t × 1)]
\(\frac{d x}{d t}\) = a[cos t + t sin t – cos t]
\(\frac{d x}{d t}\) = at sin t —— (2)
From equations (1) and (2) we get
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 20

Question 15.
x = \(\frac{1-t^{2}}{1+t^{2}}\) , y = \(\frac{2 t}{1+t^{2}}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 21

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 16.
cos-1\(\left(\frac{1-x^{2}}{1+x^{2}}\right)\)
Answer:
Let y = cos-1\(\left(\frac{1-x^{2}}{1+x^{2}}\right)\)
Put x = tan θ
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 22
y = cos-1 (cos 2θ)
y = 2θ
y = 2 tan-1 x
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 23

Question 17.
sin-1 (3x – 4x3)
Answer:
Let y = sin-1 (3x – 4x3)
Put x = sin θ
y = sin-1 (3 sin θ – 4 sin3 θ)
y = sin-1 (sin 3θ)
y = 3θ
y = 3 sin-1 x
\(\frac{d y}{d x}=\frac{3}{\sqrt{1-x^{2}}}\)

Question 18.
tan-1 \(\left(\frac{\cos x+\sin x}{\cos x-\sin x}\right)\)
Answer:
Let y = tan-1 \(\left(\frac{\cos x+\sin x}{\cos x-\sin x}\right)\)
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 24

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 19.
Find the derivative of sin x2 with respect to x2.
Answer:
Let u = sin x2
\(\frac{\mathrm{d} \mathrm{u}}{\mathrm{d} x}\) = cos (x2) × 2x
\(\frac{\mathrm{d} \mathrm{u}}{\mathrm{d} x}\) = 2x cos (x2)
Let v = x2
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 25

Question 20.
Find the derivative of sin-1\(\left(\frac{2 x}{1+x^{2}}\right)\) with respect to tan-1 x.
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 26

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 21.
If u = tan-1\(\frac{\sqrt{1+x^{2}}-1}{x}\) and v = tan-1x, find \(\frac{\mathrm{du}}{\mathrm{dv}}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 27
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 28
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 29
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 30

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 22.
Find the derivative with tan-1\(\left(\frac{\sin x}{1+\cos x}\right)\) with respect to tan-1\(\left(\frac{\cos x}{1+\sin x}\right)\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 31
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 32
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 33

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 23.
If y = sin-1x then find y”.
Answer:
y = sin-1 x
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 34

Question 24.
If y = etan-1x, show that (1 + x2) y” + (2x – 1) y’ = 0
Answer:
y = etan-1x
y = etan-1x \(\left(\frac{1}{1+x^{2}}\right)\)
⇒ y’ = \(\frac{y}{1+x^{2}}\) ⇒ y'(1 + x2) = y
differentiating w.r.to x
y’ (2x) + (1 + x2) (y”) = y’
(i.e.) (1 + x2) y” + y’ (2x) – y’ = 0
(i.e.) (1 + x2) y” + (2x – 1) y’ = 0

Question 25.
If y = \(\frac{\sin ^{-1} x}{\sqrt{1-x^{2}}}\), show that (1 – x2)y2 – 3xy1 – y = 0.
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 35
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 36

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 26.
If x = a (θ + sin θ), y = a (1 – cos θ) then prove that at θ = \(\frac{\pi}{2}\), y” = \(\frac{1}{a}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 37
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 38

Question 27.
If sin y = x sin (a + y), the prove that \(\frac{d y}{d x}=\frac{\sin ^{2}(a+y)}{\sin a}\), a ≠ nπ
Answer:
Given sin y = x sin (a + y) ——- (1)
Differentiating with respect to x , we get
cos y \(\frac{\mathrm{dy}}{\mathrm{d} x}\) = x cos (a + y) (0 + \(\frac{\mathrm{dy}}{\mathrm{d} x}\)) + sin (a + y) . 1
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 39

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4

Question 28.
If y = (cos-1 x)2, prove that (1 – x2) \(\frac{\mathrm{d}^{2} \mathrm{y}}{\mathrm{d} x^{2}}\) – x \(\frac{\mathrm{dy}}{\mathrm{d} x}\) – 2 = 0. Hence find y2 when x = 0.
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 40
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.4 41

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Maths Guide Pdf Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Maths Solutions Chapter 10 Differentiability and Methods of Differentiation Ex 10.3

Differentiate the following:

Question 1.
y = (x2 + 4x + 6)5
Answer:
Let = u = x2 + 4x + 6
⇒ \(\frac{d u}{d x}\) = 2x + 4
Now y = u5 ⇒ \(\frac{d y}{d x}\) = 5u4
∴ \(\frac{d y}{d x}=\frac{d y}{d u} \times \frac{d u}{d x}\) = 5u4 (2x + 4)
= 5(x2 + 4x + 6)4 (2x + 4)
= 5 (2x + 4) (x2 + 4x + 6)4

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3

Question 2.
y = tan 3x
Answer:
y = tan 3x
[ y = f(g(x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = sec2 3x . \(\frac{\mathrm{d}}{\mathrm{d} x}\) (3x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = sec23x × 3
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = 3 sec2 3x

Question 3.
y = cos (tan x)
Answer:
Put u = tan x
\(\frac{d u}{d x}\) = sec2x
Now y = cos u ⇒ \(\frac{d u}{d x}\) = -sin u
Now \(\frac{d y}{d x}=\frac{d y}{d u} \times \frac{d u}{d x}\)
= (-sin u) (sec2x)
= -sec2 (sin (tan x))

Question 4.
y = \(\sqrt[3]{1+x^{3}}\)
Answer:
y = \(\sqrt[3]{1+x^{3}}\)
y = (1 + x3)1/3
[ y = f(g(x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 1

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3

Question 5.
y = \(\mathrm{e}^{\sqrt{x}}\)
Answer:
y = \(\mathrm{e}^{\sqrt{x}}\)
y = \(e^{x^{\frac{1}{2}}}\)
[ y = f(g(x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 2

Question 6.
y = sin (ex)
Answer:
y = sin (ex)
[ y = f(g(x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
y = cos (ex) . \(\frac{\mathrm{d}}{\mathrm{d} x}\) (ex)
y = cos ((ex)) . ex
y = ex cos (ex)

Question 7.
F(x) = (x3 + 4x)7
Answer:
F(x) = (x3 + 4x)7
[ y = f(g(x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
F’ (x) = 7 (x3 + 4x)7 – 1 \(\frac{\mathrm{d}}{\mathrm{d} x}\) (x3 + 4x)
= 7 (x3 + 4x)6 (3x2 + 4)
= 7 (3x2 + 4) (x3 + 4x)6

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3

Question 8.
h (t) = \(\left(t-\frac{1}{t}\right)^{\frac{3}{2}}\)
Answer:
h (t) = \(\left(t-\frac{1}{t}\right)^{\frac{3}{2}}\)
[ y = f(g(x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 3

Question 9.
f(t) = \(\sqrt[3]{1+\tan t}\)
Answer:
f(t) = \(\sqrt[3]{1+\tan t}\)
f(t) = (1 + tan t)1/3
[ y = f(g(x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 4

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3

Question 10.
y = cos (a3 + x3)
Answer:
y = cos (a3 + x3)
[ y = f(g(x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = – sin (a3 + x3) \(\frac{\mathrm{d}}{\mathrm{d} x}\) (a3 + x3)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = – sin (a3 + x3) (0 + 3x2)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = – 3x2 sin (a3 + x3)

Question 11.
y = e-mx
Answer:
y = e-mx
[ y = f(g(x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = e-mx × \(\frac{\mathrm{d}}{\mathrm{d} x}\) (- mx)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = e-mx × – m
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = – m e-mx = – my

Question 12.
y = 4 sec 5x
Answer:
y = 4 sec 5x
[ y = f(g(x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = 4 × sec 5x × tan 5x \(\frac{\mathrm{d}}{\mathrm{d} x}\) (5x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = 4 sec 5x tan 5x × 5 × 1
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = 20 sec 5x tan 5x

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3

Question 13.
y = (2x – 5)4 (8x2 – 5) – 3
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 5
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 6

Question 14.
y = (x2 + 1) \(\sqrt[3]{x^{2}+2}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 7

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3

Question 15.
y = x e-x2
Answer:
y = xe-x2
y = uv where u = x and v = e-x2
Now u’ = 1 and v’ = e-x2 (-2x)
v’ = – 2xe-x2
Now y = uv ⇒ y’ = uv’ + vu’
(i.e.) \(\frac{d y}{d x}\) = x[-2xe-x2] + e-x2 (1)
= e-x2 (1 – 2x2)

Question 16.
s(t) = \(\sqrt[4]{\frac{t^{3}+1}{t^{3}-1}}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 8

Question 17.
f(x) = \(\frac{x}{\sqrt{7-3 x}}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 9

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3

Question 18.
y = tan (cos x)
Answer:
y = tan (cos x)
[ y = f(g(x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = sec2 (cos x) × \(\frac{\mathrm{d}}{\mathrm{d} x}\) (cos x)
= sec2 (cos x) × – sin x
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = -sin x . sec2 (cos x)

Question 19.
y = \(\frac{\sin ^{2} x}{\cos x}\)
Answer:
y = \(\frac{\sin ^{2} x}{\cos x}\)
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 10
= sin x (2 + tan2x)
= sin x (1 + 1 + tan2x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = sin x (1 + sec2 x)

Question 20.
y = \(5^{\frac{-1}{x}}\)
Answer:
y = \(5^{\frac{-1}{x}}\)
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 11

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3

Question 21.
y = \(\sqrt{1+2 \tan x}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 12

Question 22.
y = sin3x + cos3x
Answer:
y = sin3x + cos3x
Here u = sin3 x = (sin x)3
⇒ \(\frac{d u}{d x}\) = 3 (sin x)2 (cos x)
= 3sin2x cos x
v = cos3x = (cos x)3
⇒ \(\frac{d v}{d x}\) = 3 (cos x)2 (-sin x) = -3 sin x cos2x
Now y = u + v ⇒ \(\frac{d y}{d x}=\frac{d u}{d x}+\frac{d v}{d x}\)
= 3 sin2x cos x – 3sin x cos2x
= 3 sin x cos x (sin x – cos x)

Question 23.
y = sin2 (cos kx)
Answer:
y = sin2 (cos kx)
y = f(g(x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = 2 sin (cos kx) × cos (cos kx) × -sin kx × k × 1
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = sin (2 cos kx) × -k sin kx
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = -k sin kx . sin (2 cos kx)

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3

Question 24.
y = (1 + cos2)6
Answer:
y = (1 + cos2)6
y = f(g(x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = 6(1 + cos2x)6-1 (0 + 2 cos x × -sin x)
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = 6(1 + cos2x)5 × – 2 sin x cos x
\(\frac{\mathrm{dy}}{\mathrm{d} x}\) = -6 sin 2x (1 + cos2)5

Question 25.
y = \(\frac{e^{3 x}}{1+e^{x}}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 13
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 14

Question 26.
y = \(\sqrt{x+\sqrt{x}}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 15
[y = f(g(x))
\(\frac{\mathrm{d} \mathrm{y}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 16

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3

Question 27.
y = ex cos x
Answer:
y = ex cos x
\(\frac{\mathrm{d} \mathrm{y}}{\mathrm{d} x}\) = ex cos x (x – sinx + cos x . 1)
\(\frac{\mathrm{d} \mathrm{y}}{\mathrm{d} x}\) = ex cos x (cos x – x sin x)

Question 28.
y = \(\sqrt{x+\sqrt{x+\sqrt{x}}}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 17
[y = f(g(x))
\(\frac{\mathrm{d} \mathrm{y}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 18Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 19

Question 29.
y = sin (tan (\(\sqrt{\sin x}\)))
Answer:
y = sin (tan (\(\sqrt{\sin x}\)))
y = f(g(x))
\(\frac{\mathrm{d} \mathrm{y}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 20

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3

Question 30.
y = sin-1\(\left(\frac{1-x^{2}}{1+x^{2}}\right)\)
Answer:
y = sin-1\(\left(\frac{1-x^{2}}{1+x^{2}}\right)\)
[y = f(g(x))
\(\frac{\mathrm{d} \mathrm{y}}{\mathrm{d} x}\) = f'(g(x)) . g'(x)]
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.3 21

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Maths Guide Pdf Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Maths Solutions Chapter 10 Differentiability and Methods of Differentiation Ex 10.2

Find the derivatives of the following functions with respect to corresponding independent variables:

Question 1.
f(x) = x – 3 sin x
Answer:
f(x) = x – 3 sinx
= f'(x) = 1 – 3 (cos x)
= 1 – 3 cos x

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2

Question 2.
y = sin x + cos x
Answer:
y = sin x + cos x
\(\frac{d y}{d x}\) = cos x – sin x

Question 3.
f(x) = x sin x
Answer:
f(x) = uv
⇒ f'(x) = uv’ + vu’ = u\(\frac{d u}{d x}\) + v\(\frac{d v}{d x}\)
Now u = x ⇒ u’ = 1
v = sin x ⇒ v’ cos x
f'(x) = x (cos x) + sin x(1)
= x cos x + sin x

Question 4.
y = cos x – 2 tan x
Answer:
y = cos x – 2 tan x
\(\frac{d y}{d x}\) = – sin x – 2 sec2 x

Question 5.
g(t) = t3 cos t
Answer:
g(t) = t3 cost (i.e.) u = t3 and v = cos t
let u’ = \(\frac{d u}{d x}\) and v’= \(\frac{d v}{d x}\) = (-sint)
g'(t) = uv’ + vu’
g'(t) = t3 (-sin t) + cos t (3t2)
= -t3 sin t + 3t2 cos t

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2

Question 6.
g(t) = 4 sec t + tan t
Answer:
g(t) = 4 sec t + tan t
g'(t) = 4 sec t tan t + sec2t

Question 7.
y = ex sin x
Answer:
y = ex sin x
⇒ y = uv’ + vu’
Now u = ex ⇒ u’ = \(\frac{d u}{d x}\) ex
v = sin x ⇒ v’ = \(\frac{d v}{d x}\) cos x
i.e. y’ = ex (cos x) + sin x (ex)
= ex [sin x + cos x]

Question 8.
y = \(\frac{\tan x}{x}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 1

Question 9.
y = \(\frac{\sin x}{1+\cos x}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 2

Question 10.
y = \(\frac{x}{\sin x+\cos x}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 3

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2

Question 11.
y = \(\frac{\tan x-1}{\sec x}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 4
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 5

Question 12.
y = \(\frac{\sin x}{x^{2}}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 6

Question 13.
y = tan θ (sin θ + cos θ)
Answer:
y = tan θ (sin θ + cos θ)
\(\frac{d y}{d x}\) = tan θ (cos θ – sin θ) + (sin θ + cos 0) sec2 θ
= tan θ cos θ – tan θ sin θ + sin θ sec2θ + cos θ sec2θ
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 7
= sin θ – sin2θ sec θ + tan θ sec θ + sec θ
= sin θ + (1 – sin2θ) sec θ + sec θ tan θ
= sin θ + cos2θ × \(\frac{1}{\cos \theta}\) + sec θ tan θ
= sin θ + cos θ + sec θ tan θ

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2

Question 14.
y = cosec x . cot x
Answer:
y = cosec x . cot x
\(\frac{d y}{d x}\) = cosec x × – cosec2 x + cot x × – cosec x cot x
= – cosec3 x – cosec x cot2 x
= – cosec x (cosec2 x + cot2 x)
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 8

Question 15.
y = x sin x cos x
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 9

Question 16.
y = e-x . log x
Answer:
y = e-x . log x
\(\frac{d y}{d x}\) = e-x × \(\frac{1}{x}\) + (log x) e-x (-1)
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 10

Question 17.
y = (x2 + 5) log (1 + x) e-3x
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 11

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2

Question 18.
y = sin x0
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 12

Question 19.
y = log10 x
Answer:
y = log10 x
y = logex . log10e
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 13

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2

Question 20.
Draw the function f'(x) if f(x) = 2x2 – 5x + 3
Answer:
f(x) = 2x2 – 5x + 3
f'(x) = 4x – 5 which is a linear function
(i.e.) y = 4x – 5

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.2 16

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Maths Guide Pdf Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Maths Solutions Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

Question 1.
Find the derivatives of the following functions using the first principle.
(i) f(x) = 6
(ii) f(x) = -4x + 7
(iii) f(x) = -x2 + 2
Answer:
(i) f(x) = 6
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 1

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

(ii) f(x) = – 4x + 7,
f(x + Δx) = -4(x + Δx) + 7
f(x + Δx) – f(x) = [-4(x + Δx) + 7] – [-4x + 7]
f(x + Δx) – f(x) = [-4(x + Δx) + 7] + 4x – 7
f(x + Δx) – f(x) = -4 Δx
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 2

(iii) f(x) = -x2 + 2
f (x + Δx) = – (x + Δx)2 + 2
f (x + Δx) – f(x) = – [x2 + 2x Δx + (Δx)2] + 2 – [- x2 + 2]
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 3

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

Question 2.
Find the derivatives from the left and from the right at x = 1 (if they exist) of the following functions. Are the functions differentiable at x = 1?
(i) f (x) = |x – 1|
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 5
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 6

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

(ii) f (x) = \(\sqrt{1-x^{2}}\)
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 7
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 8
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 9
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 10

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

(iii) Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 4
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 11
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 12
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 13

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

Question 3.
Determine whether the following function is differentiable at the indicated values.
(i) f(x) = x |x| at x = 0
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 14
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 15

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

(ii) f(x) = |x2 – 1|at x = 1
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 16
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 17

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

(iii) f(x) = |x| + |x – 1| at x = 0, 1
Answer:
To find the limit at x = 0
First we find the left limit of f(x) at x = 0
When x = 0  |x| = -x and
|x – 1| = -(x – 1)
∴ When x = 0 we have
f(x) = -x – (x – 1)
f(x) = -x – x + 1 = -2x + 1
f(0) = 2 × 0 + 1 = 1
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 18
f'(0 = – 2 ……… (1)
∴When x = 0+ we have
|x| = x and |x – 1| = – (x – 1)
∴ f(x) = x – (x – 1)
f(x) = x – x + 1
f(x) = 1
f(0) = 1
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 19
From equations (1) and (2) , we get
f'(0) ≠ f’(0+)
∴ f(x) is not differentiable at x = 0.
To find the limit at x = 1
First we find the left limit of f (x) at x = 1
When x = 1 , |x| = x and
|x – 1| = -(x – 1)
∴ f(x) = x – (x – 1)
f(x) = x – x + 1 = 1
f(x) = 1
f(1) = 1
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 20
When x = 1+ , |x| = x and
|x – 1| = x – 1
When x = , |x| = x and
|x – 1| = x – 1
∴ f(x) = x + x – 1 = 2x – 1
f(1) = 2 × 1 – 1 = 2 – 1 = 1
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 21
From equations (3) and (4) , we get
f’(1) ≠ f'(1+)
∴ f (x) is not differentiable at x = 1

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

(iv) f(x) = sin |x| at x = 0
Answer:
First we find the left limit of f (x) at x = 0
When x = 0, |x| = -x
∴ f(x) = sin (-x) = -sin x
f(0) = -sin 0 = 0
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 22
Next we find the right limit of f (x) at x = 0
When x = 0+ |x| = x
∴ f(x) = sin x
f(0) = sin 0 = 0
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 23
From equations (1) and (2) , we get
f’(0) ≠ f'(0+)
∴ f (x) is not differentiable at x = 0.

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

Question 4.
Show that the following functions are not differentiable at the indicated value of x
(i) Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 24
Answer:
First we find the left limit of f(x) at x = 2
When x = 2, then x ≤ 2
∴ f(x) = -x + 2
f(2) = -2 + 2 = 0
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 25
Next we find the right limit of f(x) at x = 2
When x = 2+, then x > 2
∴ f(x) = 2x – 4
f(2) = 2 × 2 – 4 = 4 – 4 = 0
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 26
From equation (1) and (2), we get
f’(2) ≠ f'(2+)
∴ f (x) is not differentiable at x = 2

(ii) Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 27
Answer:
First we find the left limit of f (x) at x = 0
When x = 0, then x < 0
∴ f(x) = 3x
f(0) = 3 × 0 = 0
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 28
Next we find the right limit of f (x) at x = 0
When x = 0+, then x ≥ 0
∴ f(x) = -4x
f(0) = -4 × 0 = 0
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 29
From equations (1) and (2) , we get
f'(0) ≠ f'((0+)
∴ f (x) is not differentiable at x = 0

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

Question 5.
The graph of f is shown below. State with reasons that x values (the numbers), at which f is not differentiable.
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 30
Answer:
We know A function f is not differentiable at a point x0 belonging to the domain of f if one of the following situations holds
(i) f has a vertical tangent at x0
(ii) The graph of f comes to a point at x0 (either a sharp edge ∨ or a sharp peak ∧)
For the given graph f
At x = – 1 , a sharp edge ∨
At x = 8, a sharp peak ∧
At x = 4 , discontinuity
At x = 11, perpendicular tangent
∴ The given graph is not differentiable at
x = – 1, 8, 4, 11

Question 6.
If f(x) = |x + 100| + x2, test whether f’(-100) exists.
Answer:
f(x) = |x + 100| + x2
First let us find the left limit of f( x) at x = – 1100
When x < – 100 ,
f(x) = – (x + 100) + x2
f(- 100) = – (- 100 + 100) + (- 100)2
f(- 100) = 1002
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 31
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 32
= -1 – 100 – 100
f’ (-100) = -201 ——– (1)
Next let us find the right limit of f( x) at x = -100
when x > – 100
f(x) = x + 100 + x2
f(- 100) = – 100 + 100 + (- 100)2
f(- 100) = 1002
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 33
f'(-100+) = – 199 ……… (2)
From equation (1) and (2) , we get
f’(- 100) ≠ f'(- 100+)
∴ f’ (x) does not exist at x = -100
Hence, f'(- 100) does not exist

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

Question 7.
Examine the differentiability of functions in R by drawing the diagrams. (i) |sin x| (ii) |cos x|
(i) |sin x|
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 35
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 36
At the points, x = 0, π, 2π, 3π, ……….. the graph of the given function has a sharp edge V.
∴ At these points, the function is not differentiable.
∴ The function y = |sin x| is not differentiable at
x = nπ, for all n ∈ Z.
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 37

Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1

(ii) |cos x|
Answer:
Samacheer Kalvi 11th Maths Guide Chapter 10 Differentiability and Methods of Differentiation Ex 10.1 38

Samacheer Kalvi 11th English Guide Supplementary Chapter 6 The Never – Never Nest

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th English Guide Pdf Supplementary Chapter 6 The Never – Never Nest Text Book Back Questions and Answers, Summary, Notes.

Tamilnadu Samacheer Kalvi 11th English Solutions Supplementary Chapter 6 The Never – Never Nest

11th English Guide The Never – Never Nest Text Book Back Questions and Answers

B. Answer the following questions in about a paragraph of 100-150 words each:

Question 1.
Why is there a double negative in the title: The never – Never Nest? Elucidate with reasons from the play.
Answer:
Never – Never Nest is the title. It is absolutely justified because Jack and Jill, were living on a limited earning of just six pounds a month. The seed money given by Jane, as wedding gift was squandered by them in making advance payment for the house, fridge, piano etc. They continued to make EMI payments for all the items. The furniture, car and even the baby’s delivery fees was, running on EMI. There was nothing in the home they could call as completely their own.

Jack called himself the owner of the home but the EMI for the housing loan was going on and he had to continue it for many years. They are glad to be freed of the drudgery of paying rent. But they are entangled in paying EMI for the house, car, piano the bed, cot and the cozy furniture. It is very doubtful if ever the “nest” would be called a real nest. Would Jack and Jill ever become the real owners of the house and often gadgets at home is a pretty disturbing questions because Jack is borrowing every month to pay back his EMIs. Living beyond the means can never help a person to settle down in life. Such a person will have, insecurity every month.

Samacheer Kalvi 11th English Guide Supplementary Chapter 6 The Never - Never Nest

Question 2.
Bring out the humorous elements in the play.
Answer:
“The Never – Never Nest” is a comic one-act play about a young couple. They make full use of the buy – now-pay. – later marketing system. This comedy is very relevant today, because we can. buy almost anything now on the instalment basis. The author uses humour elements.

When Jane asked about the car, Jill replied that they owned steering wheel of a car and one of the tyres and about two of the cylinders belong to them. It means the car does not belong to them. When Jane was asked to lie down by Jane She replied that she was going to trust herself in a bed that belongs to Mr Sage or Marks and Spencer or somebody.

Here the author brings out the humour element at the same time makes Jack realize his mistakes. At the end of the play, humour takes on wings when we hear that the couple had their first baby in instalment.

Question 3.
How does the play “The Never-Never Nest’ expose the harsh reality of modern living?
Answer:
In modem times, plastic currency has become popular in India, as a country known for saving for future needs; a country which is proud of the adage “save for a rainy day” has undergone drastic changes. Consumer culture has eroded into every common man’s home. Credit card has swindled the younger generation of their capacity to spend hard cash. Their future earnings are pledged for purchase of luxurious things. Modem man buys things which are heavily advertised and which are often caused by jealousy. Supermarkets, Amazon, Flipkart and other online commercial organizations encourage purchase of everything ranging to laptop, electronic items and from home appliances to undergarments and shoes using credit cards.

Popular malls, Hire purchase corporate giants like Vasanth & co, Rathna Fan house offer costly consumables with a down payment of just one rupee and the rest in easy equated monthly installments. Tempted by such fabulous offers, modem men and women lose their heads and go on a spending spree. They, like Jack and Jill, spend beyond their means.

Many of them eat into their future earnings. They buy house loans and when corporate giants like Sathyam sacks young Engineers out of jobs, they end up as chain snatchers and vehicle robbers unable to payback EMIs Or credit card monthly payments. Spending on future earnings is like issuing a post-dated cheque on a crashing bank. One must be very cautious. The best way out would be to avoid immediate gratification but save money and wait until enough money is there to purchase what one wants.

Samacheer Kalvi 11th English Guide Supplementary Chapter 6 The Never - Never Nest

Question 4.
Jill said that they owned the steering wheel of a car, one of the tyres, two of the cylinders and leg of the sofa. What does this convey?
Answer:
Both Jack and Jill show their instant gratification for luxuries and had bought them on instalments without saving any money. Their life is based on buy – now – pay – later marketing system, they are not secure at all. Jill said that they owned the steering wheel of a car, one of the tyres, two of the sofa temporarily belong to them.

This situation tells that if anytime they would be unable to pay the instalments they might have to leave the house, which simply shows the insecurity of the luxuries of their life.

ஆசிரியரைப் பற்றி:

செட்ரிக் மவுண்ட் இங்கிலாந்து நாட்டைச் சார்ந்த நாடக ஆசிரியர். சிந்தனைகளை தூண்டக்கூடிய பல நாடகங்க ளை எழுதியுள்ளார். Twentieth“Century Lullaby”,“Tocutalongshort story short”,”Nature ablorsavacuum” என பலவற்றை படைத்துள்ளார்.

இவரின் ஓரங்க நாடகங்கள், நையாண்டி செய்வனவாகவும், அறிவார்ந்ததாகவும் இருக்கும். இந்த நாடகங்கள் வாழ்வின் பொய்மையை வெளிப்படுத்துகின்றது. அதை கண்டிக்கவும் செய்கிறது.

Samacheer Kalvi 11th English Guide Supplementary Chapter 6 The Never - Never Nest

கதையைப் பற்றி:

சுலப தவனைகளில் பொருள் வாங்குவதனாலும், கடன் வாங்குவதனாலும் நடுத்தர மக்கள் சந்திக்கக் கூடிய இன்னல்களை இந்த கதை நமக்கு விளக்குகிறது. தேவையின் நிமிர்த்தம் கடன் பெறுவதும், தேவையில்லாத நிலையிலும் கடன் பெறுவதிலும் மாறுதல்கள் இருக்கிறது. இதைப்பற்றி தெளிவாக இக்கதையில் காண்போம்.

The Never – Never Nest Summary in Tamil

ஜாக், ஜில், அத்தை ஜேன், செவிலி (JACK, JILL, Aunt Jane, Nurse)

நியூ ஹம்ஸ்டெட் ஊரில் உள்ள ஜாக் – ஜில் ஆகியோரின் வீடு, வீட்டில் ஒரு மேசை அதன் மேல் எழுத்து பொருட்கள், இரண்டு நாற்காலிகள், திரை உயரும் போது, ஓய்வெடுக்கும் அறை காலியாக உள்ளது. ஜாக், ஜில் உள்ளே வருகிறார்கள். அவர்களின் பின்னே அத்தை Jane வருகிறார்.

Samacheer Kalvi 11th English Guide Supplementary Chapter 6 The Never - Never Nest

JILL : ….. அப்புறமா இது தான் ஓய்வெடுக்குற இடம்….
அத்தை JANE : பிரமாதம்! பிரமாதம்! எவ்வளவு சின்ன நல்ல ரூம் அதோட நல்ல அழகான மேசை, நாற்காலி.
JACK : (நளினமாக) இது எங்களுக்கு பிடிச்சிருக்கு உட்கார நல்ல இடம். ரேடியோவும் கேட்டுக்கலாம்.
அத்தை Jane : நீங்க ரேடியோ, கார், அத்தோட பியானோ இதையெல்லாம் வாங்கிட்டீங்களா?
JACK : ஆமா அத்தை இப்பெல்லாம் ஒரு ரேடியோ கண்டிப்பா வெச்சுருக்கணும்.
JILL : ஜாக் வேலைக்கு போயிட்டா, இது கேட்க நல்லா இருக்கு, அவர் கிட்ட சொல்லி இதை சமையலறைக்குள்ள கொண்டு வரச் சொல்வேன் சமையல் செய்யும் போது, ரேடியோ கேட்பேன்.

JACK : உட்காருங்க, அத்தை. நீங்க சோர்வா இருப்பீங்க நாங்க எங்க வீடு எல்லாம் சுத்திக் காட்டிட்டோம்.
JILL : எங்க சின்ன கூட்டைப்பத்தி என்ன நினைக்கிறீங்க அத்தை.
AUNT JANE : இது ரொம்ப அழகாக இருக்கு., இந்த மேசை, நாற்காலி. அப்புறம். கார்… அப்புறமா பியோனா, பிரிட்ஜ், ரேடியோ அது என்ன…? ரொம்ப பிரமாதம்!
JACK : இது எல்லாம் எங்களுக்கு வந்தது உங்களால் தான்.
AUNT JANE : ஆமா, ஜாக். அதுதான் எனக்கு கவலையா இருக்கு.
JACK : என்ன அத்தை, கவலையா இருக்கா?
AUNT JANE : நான் கல்யாணத்தன்னிக்கு உங்களுக்கு அன்பளிப்பா, ஒரு செக் கொடுத்தேன் பாருங்க. அது இருநூறு பவுண்டு தான்! இல்லையா? நான், அதுல ரெண்டாயிரம் பவுண்டுன்னு எழுதலையே!
JILL : இல்ல ஜேன்! எப்படி உங்களுக்கு அப்படி ஒரு சந்தேகம் வந்துச்சு?

Samacheer Kalvi 11th English Guide Supplementary Chapter 6 The Never - Never Nest

AUNT JANE : பரவாயில்ல, இருக்கட்டும். ஆனா, இன்னமும் எனக்கு ஒண்ணு புரியல. இந்த வீடு, இது ரொம்ப நல்லா இருக்கு… ஆனா, இதுக்கான வாடகை ரொம்ப அதிகமா இருக்குமே!
JACK : வாடகையா? இல்ல.. இல்ல.. நாங்க வாடகை கொடுக்கிறது இல்லை.
AUNT JANE : ஆனாஜாக், நீவாடகைகுடுக்கலேன்னா, உன்னையதெருவுக்குதள்ளிவிட்டுருவாங்களே! அது சரியில்ல. இப்ப, உனக்கு ஜில், அதோட ஒரு குழந்தை .. அதை நீ மனசுல வெச்சுக்கணும்.
JACK : இல்ல.. இல்ல.. அத்தை … நீங்க என்னைய தவறா புரிஞ்சுக்கிட்டீங்க. நாங்க வாடகை எதுவும் கொடுப்பதில்லை. ஏன்னா, இந்த வீடு எங்களுடையது.
AUNT JANE : உங்களோடதா?
JILL : ஆமா, பத்து பவுண்டு பணம் கட்டுனா, இந்த வீடு என்னோடது தான்.
JACK : இங்க பாருங்க அத்தை பத்து பவுண்டு பணம் கட்டுனா, நமக்கு சொந்தமா, ஒரு வீட்டையே வாங்குற போது, வருசா .. வருசம் … வாடகை கட்டிக்கிட்டு இருக்கறது சிக்கனமானது. இல்லை இதை நாங்க புரிஞ்சிக்கிட்டோம். அத்தோட, கால் வருட தொகை கட்டணும். அதான் பார்த்தேன். வாடகைக்காரனா குடியிருக்கறதை விட, ஓனரா இருக்கலாமே!
AUNT JANE : சரி. அதுல ஏதோ இருக்கு. இருந்தாலும் நீங்க நல்ல சம்பாதிச்சாத்தான் இப்படி ஒரு இடத்துல இருக்க முடியும்.
JILL : ஓ, ஆமா அத்தை. போன வருஷம் தான் இவருக்கு அஞ்சு ஷில்லிங் சம்பளம் கூட்டினார்கள் இல்லையா, ஜாக்?

JACK : (நளினமாக) ஆமா, அது ஒண்ணுமில்ல. இந்த கிறிஸ்மஸ்ல எனக்கு பத்து ஷில்லிங் சம்பளம் கூட்டித்தருவாங்க.
AUNT JANE : திடீரென) ஜாக்! இப்பதான் அதைப்பத்தி யோசிச்தேன் அந்த கார். அது உண்மையில உன்னோடது தானா?
JILL : ஆமா, அது என்னோடது தான்.
AUNT JANE : எல்லா காருமா?
JACK : அது வந்து, எல்லா காரும் இல்ல.
AUNT JANE : அப்ப அது எவ்வளவு?
JILL : உண்மையா சொல்லப்போனா, அந்த ஸ்டியரிங் அப்புறம் ஒரு டயர். அதுல இருக்கிற ரெண்டு சிலிண்டர். இவ்வளவு தான் எங்களுக்கு சொந்தம். ஆனா, அது ரொம்ப . அற்புதமானது இல்லையா?

Samacheer Kalvi 11th English Guide Supplementary Chapter 6 The Never - Never Nest

JACK : உட்காருங்க, அத்தை. நீங்க சோர்வா இருப்பீங்க நாங்க எங்க வீடு எல்லாம் சுத்திக் காட்டிட்டோம்.
JILL : எங்க சின்ன கூட்டைப்பத்தி என்ன நினைக்கிறீங்க அத்தை.
AUNT JANE : இது ரொம்ப அழகாக இருக்கு., இந்த மேசை, நாற்காலி. அப்புறம். கார்… அப்புறமா பியோனா, பிரிட்ஜ், ரேடியோ அது என்ன…? ரொம்ப பிரமாதம்!
JACK : இது எல்லாம் எங்களுக்கு வந்தது உங்களால் தான்.
AUNT JANE : ஆமா, ஜாக். அதுதான் எனக்கு கவலையா இருக்கு.
JACK : என்ன அத்தை, கவலையா இருக்கா?
AUNT JANE : நான் கல்யாணத்தன்னிக்கு உங்களுக்கு அன்பளிப்பா, ஒரு செக் கொடுத்தேன் பாருங்க. அது இருநூறு பவுண்டு தான்! இல்லையா? நான், அதுல ரெண்டாயிரம் பவுண்டுன்னு எழுதலையே!
JILL : இல்ல ஜேன்! எப்படி உங்களுக்கு அப்படி ஒரு சந்தேகம் வந்துச்சு?
AUNT JANE : பரவாயில்ல, இருக்கட்டும். ஆனா, இன்னமும் எனக்கு ஒண்ணு புரியல. இந்த வீடு, இது ரொம்ப நல்லா இருக்கு… ஆனா, இதுக்கான வாடகை ரொம்ப அதிகமா இருக்குமே!

JACK : வாடகையா? இல்ல.. இல்ல.. நாங்க வாடகை கொடுக்கிறது இல்லை.
AUNT JANE : ஆனாஜாக், நீவாடகைகுடுக்கலேன்னா, உன்னையதெருவுக்குதள்ளிவிட்டுருவாங்களே! அது சரியில்ல. இப்ப, உனக்கு ஜில், அதோட ஒரு குழந்தை .. அதை நீ மனசுல வெச்சுக்கணும்.
JACK : இல்ல.. இல்ல.. அத்தை … நீங்க என்னைய தவறா புரிஞ்சுக்கிட்டீங்க. நாங்க வாடகை எதுவும் கொடுப்பதில்லை. ஏன்னா, இந்த வீடு எங்களுடையது.
AUNT JANE : உங்களோடதா?

Samacheer Kalvi 11th English Guide Supplementary Chapter 6 The Never - Never Nest

JILL : ஆமா, பத்து பவுண்டு பணம் கட்டுனா, இந்த வீடு என்னோடது தான்.
JACK : இங்க பாருங்க அத்தை பத்து பவுண்டு பணம் கட்டுனா, நமக்கு சொந்தமா, ஒரு வீட்டையே வாங்குற போது, வருசா .. வருசம் … வாடகை கட்டிக்கிட்டு இருக்கறது சிக்கனமானது. இல்லை இதை நாங்க புரிஞ்சிக்கிட்டோம். அத்தோட, கால் வருட தொகை கட்டணும். அதான் பார்த்தேன். வாடகைக்காரனா குடியிருக்கறதை விட, ஓனரா இருக்கலாமே!
AUNT JANE : சரி. அதுல ஏதோ இருக்கு. இருந்தாலும் நீங்க நல்ல சம்பாதிச்சாத்தான் இப்படி ஒரு இடத்துல இருக்க முடியும்.
JILL : ஓ, ஆமா அத்தை. போன வருஷம் தான் இவருக்கு அஞ்சு ஷில்லிங் சம்பளம் கூட்டினார்கள் இல்லையா, ஜாக்?
AUNT JANE : (நளினமாக) ஆமா, அது ஒண்ணுமில்ல. இந்த கிறிஸ்மஸ்ல எனக்கு பத்து ஷில்லிங் சம்பளம் கூட்டித்தருவாங்க. திடீரென) ஜாக்! இப்பதான் அதைப்பத்தி யோசிச்தேன் அந்த கார். அது உண்மையில உன்னோடது தானா?
JILL : ஆமா, அது என்னோடது தான்.
AUNT JANE : எல்லா காருமா?
JACK : அது வந்து, எல்லா காரும் இல்ல.
AUNT JANE : அப்ப அது எவ்வளவு?
JILL : உண்மையா சொல்லப்போனா, அந்த ஸ்டியரிங் அப்புறம் ஒரு டயர். அதுல இருக்கிற ரெண்டு சிலிண்டர். இவ்வளவு தான் எங்களுக்கு சொந்தம். ஆனா, அது ரொம்ப. அற்புதமானது இல்லையா?

AUNT JANE : இதுல என்ன அற்புதம்ன்னு எனக்கு தெரியல.
JILL : ஆனா, அதுல ஒரு அற்புதம் இருக்கு. நாம ஒரு காரையே வாங்க முடியலைன்னாலும், அஞ்சு பவுண்டு குடுத்தா, அதை ஜாலியா ஓட்டலாம் இல்லையா?
AUNT JANE : மத்ததெல்லாம், சுலப தவணைகள், என்று நான் நினைக்கிறேன்.
JILL: சரியா சொன்னீங்க.
AUNT JANE : சரி, அந்த ரேடியோ எப்படி? அது என்ன!…..
JACK: அது…. அது……
AUNT JANE : அப்புறமா பியானோ.
JILL: ஆமா.
AUNT JANE : அப்புறம், மேசை நாற்காலி.
JACK : ஆமா… அதுவும், அப்படித்தான்…
JILL : நல்லது. அங்க ஒண்ணு இருக்கே … (எதையோ கை காட்டுகிறார்).
AUNT JANE : மத்ததெல்லாம், மிஸ்டர் சேஜ்க்கு சொந்தமானது இல்லையா?
JILL: ஆமா.

Samacheer Kalvi 11th English Guide Supplementary Chapter 6 The Never - Never Nest

AUNT JANE : நல்லது மிஸ்டர் சேஜ்க்கு சொந்தமான எதிலேயும் நான் உக்கார மாட்டேன். (அவர் எழுந்து நிற்கிறார்). இப்ப சொல்லுங்க இந்த மொத்த தவணை எல்லாம் மொத்தம் எவ்வளவு வருது?
JACK : அது வந்து, உண்மையில.. (அவன் தன்னுடைய சட்டைப்பாக்கெட் நோட்டை எடுத்து, அதைப் பார்க்கிறான்).. ஒரு வாரத்துக்கு ஏழு பவுண்டு எட்டு ஷில்லிங், எட்டு பென்னி.
AUNT JANE : கடவுளே! நீ எவ்வளவு சம்பாதிக்கற?
JACK : சொல்லப்போனா, வந்து … ஆறு பவுண்டு.
AUNT JANE : ஆனா, இது ரொம்ப முட்டாள்தனம் ஆறு பவுண்டு சம்பளத்தை வைத்து எப்படி ஏழு பவுண்டு எட்டு ஷில்லிங், எட்டு பென்னி கடனை கட்டுவீங்க?
JACK : ஓ.. அது ரொம்ப ஈஸி, அதுல பாருங்க. நமக்கு அதிகமா தேவைப்படுற பணத்தை “த்ரிப்ட் அண்ட் ப்ரொவிடென்ஸ் டிரஸ்ட் கார்பொரேஷன்”ல கடனா வாங்கிக்க வேண்டியது தான்.
JILL : அவங்க எவ்வளவு கடன் கேட்டாலும், தர்றாங்க அங்க ப்ரோ – நோட் எழுதி தரவேண்டும்.
AUNT JANE : சரி இதை எப்படி திரும்பி கட்டப்போறீங்க?
JACK : ஓ, அதுவும் ரொம்ப ஈஸி, அதை தவணையில திரும்பி கட்டணும்.
AUNT JANE : தவணையா! (அவள் தனது தலையில் கையை வைத்துக் கொண்டு நாற்காலியில் உட்கார்ந்து விடுகிறாள். பிறகு, அது மிஸ்டர் சேஜ்க்கு சொந்தமானது என்பதை உணர்ந்து உடனே அலறிக்கொண்டு, கால்களால் குதித்து தரையில் நிற்கிறாள்))
JACK : அத்தை என்னாச்சு? நீங்க படுத்துக்க விரும்புறீங்களா!
AUNT JANE : இங்கயா?அந்த மிஸ்டர் சேஜ் அல்லது மார்க்ஸ் அல்லது ஸ்பென்ஸர்க்கு அல்லது வேற யாருக்காவது, சொந்தமான படுக்கையில் விழுந்து கிடப்பேன்னு நினைக்கிறீங்களா? இல்ல, நான் வீட்டுக்குப் போறேன்.
JILL : ஓ, நீங்க போயே ஆகணுமா?
AUNT JANE : அதுதான் நல்லதுன்னு நினைக்கிறேன்.
JACK : நான் உங்கள என் கார்ல கூட்டிக்கிட்டுப் போயி ஸ்டேஷன்ல விடுறேன்.
AUNT JANE : ஒரு டயர், ரெண்டு சாமான் மட்டுமே இருக்கிற கார்ல போகணுமா? வேணாம் நன்றி, நான் பஸ்ல போயிக்கிறேன்.
JACK : நல்லது, அதுதான் உங்களோட முடிவுன்னா சரி.

Samacheer Kalvi 11th English Guide Supplementary Chapter 6 The Never - Never Nest

AUNT JANE : நான் கொஞ்சம் கடுமையா பேசினதுக்கு வருத்தப்படுறேன். (சிறிது வருத்தத்துடன்) நீங்க குடும்பம் நடத்துறவிதத்தை பாத்துட்டு, நான் அதிர்ச்சியடைஞ்சுட்டேன். என் வாழ்க்கையில ஒருத்தருக்கும் ஒரு பைசா கடன் கொடுக்கிற மாதிரி நான் இருக்கல. உடனடி ரொக்கம் அதுதான் என் கொள்கை நீங்களும் அதே மாதிரி இருக்கணும்னு நான் விரும்பறேன்.

(தனது கைப்பையைத் திறந்து) இங்க பாருங்க! உங்களுக்காக நான் கொடுக்கணும்னு “வெச்சுருந்த ஒரு சின்ன தொகைக்கான செக். (அதை ஜில்லிடம் கொடுத்து விட்டு இதை வெச்சுக்கிட்டு, நீங்க உங்களோட தவணையை கட்டி, குறைஞ்ச பட்சம் ஒரு சாமானாவது உங்களுக்கு சொந்தமாகுற மாதிரி செய்வீங்கன்னு நினைக்கிறேன்.

JILL : வந்து…. நன்றி அத்தை நீங்க செஞ்சது ரொம்ப நல்லதா இருக்கு.
AUNT JANE : சரி. நான் போகணும் (அவனது கையை தட்டிக் கொடுக்கிறார்)
JACK : உங்களை நான் பஸ் வரை வந்து வழியனுப்புகிறேன்.
JILL : குட்பை அத்தை, உங்க அன்பளிப்புக்கு நன்றி.

AUNT JANE : குட்பை கண்ணு! (அவளும் ஜாக்கும் வெளியே போகிறார்கள். ஜில், அந்த செக்கை பார்த்து விட்டு, காற்றில் பறக்கும் முத்தமிடுகிறாள். பிறகு “பத்து பவுண்டா!” என்று ஆச்சரியத்தில் கத்துகிறாள். பிறகு மேசைக்கு சென்று, ஒரு தபால் உறை எடுத்து, அதன்மேல், ஒரு விலாசத்தை எழுதுகிறாள். அந்த செக்கை வேறொருவருக்கு பெயர் மாற்றம் செய்கிறாள். அந்த செக்குடன் ஒரு ரசீதை இணைத்து அதை அந்த தபால் உறையினுள் போடுகிறாள். பிறகு மணியடிக்கிறாள். ஒரு செவிலி ஒருநொடியில் அங்கு கையில் குழந்தையுடன் வருகிறாள்.)

JILL : ஓ, நர்ஸ், உடனே ஓடிப்போய், இதை தபால்ல போட்டுட்டு வா, நீ போயிட்டு திரும்பும் வரை, நான் குழந்தையை பார்த்துக்கிறேன்.
NURSE : கண்டிப்பாக, மேடம் (தன் கையில் இருக்கும் குழந்தையை, அவள் ஜில்லிடம் தந்து விட்டு, கடிதத்தை வாங்கிக்கொண்டு போகிறாள்).
JACK : நல்லது அத்தை போயிட்டா! என்ன ஒரு எரிச்சலாக்குற ஆளு! இருந்தாலும், அவ கொஞ்சம் பணம் கொடுத்துவிட்டு போயிருக்கா. அது எவ்வளவு?
JILL : பத்து பவுண்டு
JACK : ஓ.. அது ரொம்ப அருமை…! நாம, அந்த காருக்கு அடுத்த ரெண்டு மாசத்துல கட்ட வேண்டிய தவணைக்கு இதை கட்டிவிடலாம் (விசில் அடிக்கிறான்)
JILL : நாம அதை அப்படி செய்ய முடியாது.
JACK : ஏன் முடியாது?

Samacheer Kalvi 11th English Guide Supplementary Chapter 6 The Never - Never Nest

JILL : இங்க பாருங்க, அதை வேற ஒண்ணுக்காக கொடுத்து அனுப்பிட்டேன். நம்ம நர்ஸ் அதை எடுத்துக்கிட்டு தபால்ல போட போயிருக்காங்க.
JACK : நல்லது அது சரி தான்! யாருக்கு அதை அனுப்பிச்சுருக்க.
JILL : டாக்டர் மார்ட்டின்.
JACK : டாக்டர் மார்ட்டினா! நீ என்ன பிசாசு பிடிச்சு இப்படி செய்யுறியா?
JILL : (அழும் நிலையில்) பாருங்க! என் மேல கோபப்படுறீங்க!.
JACK : நான் கோபப்படல, ஆனா, ஏன் இவ்வளவு பணத்தை டாக்டருக்கு கொடுக்கிறீங்க? டாக்டர் பணம் குடுப்பாங்கன்னு எதிர்பார்த்து இருக்க மாட்டாங்க.
JILL : (சிறிது அழுகிறார்) ஆனா…. ஆனா…. நீங்க புரிஞ்சுக்க மாட்டுறீங்க!
JACK : என்ன புரிஞ்சுக்கல?
JILL : இன்னும்… ஒரே ஒரு தவணை தான் உள்ளது. அப்புறம் இந்த குழந்தை நமக்கு சொந்தம். (அவள், கொஞ்சம் பரிதாபமாக, குழந்தையை எடுத்து முன்னே நீட்டிக்காட்டுகிறாள். நாம் இருளடைகிறோம்)