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Class 12 Maths MCQ Questions of Integrals with Answers?

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To help the students in their preparations, Class 12 Maths MCQ Questions of Integrals with Answers were created by subject specialists as per exam pattern and syllabus. The ideas of integrals are given in an exhaustive and straightforward manner. These Important MCQ Questions are exceptionally straightforward and can without much of a stretch help students in learning the interaction of problem-solving.

As per the new syllabus, Integration Important Multiple Choice Questions for Class 12 gives you the most recent Questions and solutions. To help you better, students can clarify every one of their questions about every part by practicing these significant Questions and careful clarifications given by our specialists. These Questions will assist students with preparation for the tests. The chapter-wise strategy for planning for your board assessment offers you Integration Important MCQ Questions for Class 12.

Practice MCQ Question for Class 12 Maths chapter-wise

 1. ∫ 1+sinx/1+cosx . ex dx is equal to

(a) etan(x/2)+k
(b) ex tanx+k
(c) 1/2ex tan(x/2)+k
(d) ex sec2(x/2)+k

2. \(\int\frac{2^x}{\sqrt{1-4^x}}dx\) = K sin-1(2x)+C, then K is equal to

(a) ln2
(b) 1/2 ln2
(c) 1/2
(d) 1/ln2

3. If \(\int\frac{2^{1/x}}{x^2}dx=\) k.21/x+C, then k is equal to

(a) -1/loge2
(b) -loge2
(c) -1
(d) 1/2

4. \(\int\frac{1}{sin^2xcos^2x}dx\) is equal to

(a) sin2 x – cos2 x + C
(b) -1
(c) tan x + cot x + C
(d) tan x – cot x + C

5. \(\int\frac{cos2x-cos2\theta}{cosx-cos\theta}dx\) is equal to

(a) 2(sin x + x cos θ) + C
(b) 2(sin x – x cos θ) + C
(c) 2(sin x + 2x cos θ) + C
(d) 2(sin x – 2x cos θ) + C

6. ∫cot2x dx equals to

(a) cot x – x + C
(b) cot x + x + C
(c) -cot x + x + C
(d) -cot x – x + C

7. \(\int\frac{sinx+cosx}{\sqrt{1+sin2x}}dx,\frac{3\pi}{4}<x<\frac{7\pi}{4}\) is equal to

(a) log |sin x + cos x|
(b) x
(c) log |x|
(d) -x

8. If ∫ sec2(7 – 4x)dx = a tan (7 – 4x) + C, then value of a is

(a) 7
(b) -4
(c) 3
(d) −1/4

9. The value of X for which

\(\int\frac{4x^3+\lambda4^x}{4^x+x^4}dx=log|4^x+x^4|is\)

(a) 1
(b) loge4
(c) loe4 e
(d) 4

10. If \(\int\frac{1}{\sqrt{4-9x^2}}dx=\frac{1}{3}sin^{-1}(ax)+C,\) then value of a is

(a) 2
(b) 4
(c) 3/2
(d) 2/3

11. \(\int\frac{10x^9+10^xlog_e10}{x^{10}+10^x}dx\) equals

(a) 10x -x10 + c
(b) 10x + x10 + c
(c) (10x – x10)-1 + c
(d) log (10x + x10) + c.

12. \(\int\frac{e^x(1+x)}{cos^2(xe^2)}dx \) is equals to

(a) -cot (xex) + c
(b) tan (xex) + c
(c) tan (ex) + c
(d) cot (ex) + c

13. If \(\int\frac{1}{(x^2+4)(x^2+9)}dx=A\,tan^{-1}\frac{x}{2}+B\,tan^{-1}(\frac{x}{3})\) +C then A-B =

(a) 1/6
(b) 1/30
(c) -1/30
(d) -1/6

14. The value of \(\int\frac{e^x(x^2tan^{-1}x+tan^{-1}x+1)}{x^2+1}\)  dx is equal to

(a) extan-1x+C
(b) tan-1(ex)+C
(c) tan-1(xe)+C
(d) etan^-1x+C

15. If ∫ dx/[(x+2)(x2+1)] =  a log |1 + x2| + b tan–1x + (1/5) log |x + 2| + C, then 

(a) a = -1/10, b = -2/5 
(b) a = 1/10, b = -2/5 
(c) a = -1/10, b = 2/5 
(d) a = 1/10, b = 2/5

16. \(\int x^2e^{x^3}\) dx equals

(a) 1/3 ex^3+C
(b) 1/3 ex^4+C
(c) 1/2 ex^3+C
(d) 1/2 ex^2+C

17. ∫ex sec x (1 + tan x) dx equals

(a) ex cos x + c
(b) ex sec x + c
(c) ex sin x + c
(d) ex tan x + c.

18. ∫tan-1 √x dx is equal to

(a) (x + 1)tan-1 √x – √x + c
(b) x tan-1 √x – √x + c
(c) √x – x tan-1 √x + c
(d) tan-1x – (x + 1) tan-1 √x + c

19. ∫ex(cosx−sinx)dx is equal to

(a) ex cosx + C
(b) ex sinx + C
(c) -ex cosx + C
(d) -ex sinx + C

20. If a is such that \(\int_0^axdx\) ≤ a + 4, then

(a) 0 ≤ a ≤ 4
(b) -2 ≤ a ≤ 0
(c) a ≤ -2 or a ≤ 4
(d) -2 ≤ a ≤ 4

Answer: 

1. Answer: (a) etan(x/2)+k

Explanation: \(\int\frac{1+sin\,x}{1+cos\,x}.e^xdx\)

Use \(cos\,x=\frac{1-tan^2(x/2)}{1+tan^2(x/2)},sin\,x=\frac{2tan(x/2)}{1+tan^2(x/2)}\)

The integral becomes

\(=\int\frac{1+tan^2(x/2)+2\,tan(x/2)}{1+tan^2(x/2)+1-tan^2(x/2)}.e^xdx\)

\(=\int\frac{sec^2(x/2)+2\,tan(x/2)}2.e^xdx\)

\(=\int\left[\frac12sec^2(x/2)+tan(x/2)\right]e^xdx\)

If we take tan (x/2) = f(x), the equation takes the form

\(\int e^x\) [f(x) + f'(x)]dx

\(=e^x\) f(x) + k

\(=e^x\) tan (x/2) + k

2. Answer: (d) 1/ln2

Explanation: \(I=\int\frac{2^x}{\sqrt{1-4^x}}dx\)

Let \(2^x\) = z

\(\Rightarrow\) \(2^x\) log 2dx = dz

\(\Rightarrow\) \(I=\int\cfrac{\frac1{log\,2}}{\sqrt{1-z^2}}dz\)

\(=\frac1{log\,2}.sin^{-1}z+c\)

\(=\frac1{log\,2}.sin^{-1}(e^x)+c\)

\(=k\,sin^{-1}(2^x)+c\)

then k \(=\frac1{log\,2}.\)

3. Answer: (a) -1/loge2

Explanation: \(I=\int\frac{2^{\frac1x}}{x^2}dx=k.2^{\frac1x}+C\;\;...(1)\)

Let \(\frac1x\) = t

\(\Rightarrow\) \(\frac{-1}{x^2}dx=dt\)

\(\Rightarrow\) \(\frac{dx}{x^2}\) = -dt

Put \(\frac1x\) = t and \(\frac{dx}{x^2}\) = -dt  ....in LHS of equation (1) we get

\(I=-\int2^t.dt\)

\(=-\frac{2^t}{In\,2}+C\)

\(=-\frac{2^{\frac1x}}{In\,2}+C\;\;...(2)\)

Comparing of RHS of equation (1) with equation (2) we get

\(k=-\frac1{In\,2}\)

\(\therefore\) \(k=-\frac1{log_e\,2}\)

4. Answer: (d) tan x – cot x + C

Explanation: \(\int\frac1{sin^2x\,cos^2x}dx\)

\(=\int\frac{sin^2x+cos^2x}{sin^2x\,cos^2x}dx\)

\(=\int(sec^2x+cosec^2x)dx\)

= tan x - cot x + C

5. Answer: (a) 2(sin x + x cos θ) + C

Explanation: as \(\int\frac{2(cos^2x-cos^2\theta)}{cos\,x-cos\,\theta}dx,\)

using cos 2x = 2 \(cos^2x\) - 1

= 2 \(\int(cos\,x+cos\,\theta)dx\)

= 2 sin x + 2x . cos \(\theta\) + C

6. Answer: (d) -cot x – x + C

Explanation: ∫ (cosec2x -1)dx = -cot x – x + C

7. Answer: (d) -x

Explanation: as \(\int\frac{sin\,x+cos\,x}{|sin\,x+cos\,x|}dx,\)

\(\Rightarrow\) \(-\int\) 1.dx = -x + C

{as sin x + cos x < 0 for \(\frac{3\pi}{4}<x<\frac{7\pi}{4}\}\)

8. Answer: (d) −1/4

Explanation: \(\int sec^2(7-4x)dx=\frac{tan(7-4x)}{-4}+C\)

\(=-\frac14\) tan (7 - 4x) + C.

9. Answer: (b) loge4

Explanation: \(as\,\frac d{dx}log|4^x+x^4|=\frac1{4^x+x^4}.(4^x.log_e4+4x^3)\) \(=\frac{4x^3+log_e\,4.4^x}{4^x+x^4}\)

\(\Rightarrow\lambda=log_e\,4\)

10. Answer: (c) 3/2

Explanation: \(as\int\frac1{\sqrt{4-9x^2}}dx=\frac13\int\frac1{\sqrt{(\frac23)^2-x^2}}dx\)

\(=\frac13sin^{-1}(\frac{3x}2)+C\)

\(\Rightarrow a=\frac32.\)

11. Answer: (d) log (10x + x10) + c.

Explanation: Given:

\(\int\frac{(10x^9+10x\,In\,10)dx}{(x^{10}+10^x)}\)

To evaluate

take \(y=x^{10}+10^x\)

\(\frac{dy}{dx}=10x^9+10x\,In\,10\)

\(dy=(10x^9+10^x\,In\,10)\;dx\)

\(\therefore\) \(I=\int\frac{dy}y=In\,y\)

Hence, the correct answer is \(In|(x^{10}+10^x)|\)

12. Answer: (b) tan (xex) + c

Explanation: Let \(I=\int\frac{e^x(1+x)}{cos^2(xe^x)}dx\)

Put \(x.e^x\) = t

Diff.w.r.t..x

\(\therefore\) \(x.e^x+e^x.1=\frac{dt}{dx}\)

\(\therefore\) \(e^x(1+x)dx=dt\)

\(\therefore I=\int\frac{dt}{cos^2t}=\int sec^2tdt\)

\(\therefore\) tan t + c

\(=tan(x.e^x)+e\)

13. Answer: (a) 1/6

Explanation: Given :

\(\therefore\) \(\int\frac1{(x^2+4)(x^2+9)}dx\) \(=A\,tan^{-1}\frac x2+B\,tan^{-1}\frac x3+C\;\;...(i)\)

\(\frac1{AB}=\frac1{B-A}(\frac1{A}-\frac1{B})\)

\(\therefore\) \(\int\frac1{(x^2+4)(x^2+9)}dx\) \(=\int\frac1{5}(\frac1{x^2+4}-\frac1{x^2+9})dx\)

\(=\frac1{5}\left[\frac1{2}tan^{-1}\frac x{2}-\frac1{3}tan^{-1}\frac x{3}\right]+C\)

\(=\frac1{10}tan^{-1}\frac x{2}-\frac1{15}tan^{-1}\frac x{3}+C\)

Comparing above equation with (i) we get

A = \(\frac1{10}\) and B = \(-\frac1{15}\)

\(\therefore\) A - B \(=\frac{1}{10}+\frac{1}{15}=\frac{5}{30}=\frac{1}{6}\)

14. Answer: (a) extan-1x+C

Explanation: \(\int\frac{e^x(x^2tan^{-1}x+tan^{-1}x+1)}{x^2+1}dx\) \(=\int\frac{e^x[(x^2+1)\,tan^{-1}x)+1]}{x^2+1}dx\)

\(=\int e^x(tan^{-1}x+\frac{1}{1+x^2})dx\) \(=e^xtan^{-1}x+c\)

Note : \(\int\) \(e^x\)[f(x) + f'(x)] dx = \(e^x\) f(x) + c

Here f(x) = \(tan^{-1}x\)

15. Answer: (c) a = -1/10, b = 2/5 

Explanation: \(I=\int\frac{dx}{(x+2)(x^2+1)}\)

\(\frac{1}{(x+2)(x^2+1)}=\frac A{x+2}+\frac{Bx+C}{x^2+1}\)

\(\Rightarrow\) 1 = A(\(x^2\)+1) + (Bx+C) (x+2)

\(\Rightarrow\) 1 = (A+B)\(x^2\) + (2B+C)x + A + 2C

Comparing coefficients, we get

A+B = 0, A+2C = 1, 2B+C = 0

Solving we get A = \(\frac15\), B = \(-\frac15\) and C = \(\frac25\)

\(\therefore\) \(\int\frac{dx}{(x+2)(x^2+1)}\)

\(=\frac15\int\frac1{x+2}dx+\int\cfrac{-\frac{1}{5}x+\frac{2}{5}}{x^2+1}dx\)

\(=\frac15\int\frac1{x+2}dx-\frac1{10}\int\frac{2x}{1+x^2}dx+\frac15\int\frac{2}{1+x^2}dx\)

\(=\frac15log|x+2|-\frac1{10}log|1+x^2|\) \(+\frac25tan^{-1}x+C\)

\(=a\,log|1+x^2|+b\,tan^{-1}x\) \(+\frac15\,log|x+2|+C\) (given)

\(\therefore\) \(a=\frac{-1}{10},b=\frac25\)

16. Answer: (a) 1/3 ex^3+C

Explanation: \(\int x^2e^xdx\)

Let \(x^3\) = t

\(\Rightarrow\) \(3x^2=\frac{dt}{dx}\)

\(\Rightarrow dx=dt/3x^2\)

\(\therefore\) \(\int x^2\times e^t\times\frac{dt}{3x^2}\)

\(=\frac13\int e^tdt\)

\(=\frac13e^t+c\)

\(=\frac13\times e^{x^3}+c\)

17. Answer: (b) ex sec x + c

Explanation: Let \(I=\int e^x\) sec x (1+tan x)dx

\(=\int e^x\) (sec x + sec x tan x)dx

Also, let sec x = f(x)

\(\Rightarrow\) sec x tan x = f'(x)

We know that,

\(\int e^x\) {f(x) + f'(x)} = \(e^x\) f(x) + C

\(\therefore\) I = \(e^x\) sec x + C

18. Answer: (a) (x + 1)tan-1 √x – √x + c

Explanation: \(\int tan^{-1}\;\sqrt xdx\)

Apply integration by parts

\(x\int tan^{-1}\;\sqrt x-\int\frac x{2(1+x)\sqrt x}dx\)

\(x\int tan^{-1}\;\sqrt x-\frac12\int\frac{\sqrt x}{1+x}dx\)

Let \(\sqrt x\) = t

\(\frac{dx}{2\sqrt x}=dt\)

dx = 2tdt

\(=x\,tan^{-1}\;\sqrt x-\int\frac{t^2}{1+t^2}dt\)

\(=x\,tan^{-1}\;\sqrt x-\int dt+\int\frac{1}{1+t^2}dt\)

\(x\,tan^{-1}\;\sqrt x-\sqrt x+tan^{-1}\sqrt x+c\)

\(=(x-1)tan^{-1}\sqrt x-\sqrt x+c\)

19. Answer: (a) ex cosx + C

Explanation: since \(\int e^x\) (f(x) + f'(x))dx = \(e^x\) f(x) + C

Here f(x) = cos x, f'(x) = -sin x. 

So, \(\int e^x\) (cos x - sin x)dx = \(e^x\) cos x + C

20.  Answer: (d) -2 ≤ a ≤ 4

Explanation: as \(\int_0^axdx\) ≤ a + 4
⇒ a2/2 ≤ a + 4
⇒ a2 – 2a — 8 ≤ 0
⇒ (a – 1)2 ≤ (3)2
⇒ -3 ≤ a – 1 ≤ 3
⇒ -2 ≤ a ≤ 4

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