Free NCERT Solutions for Class 12 Maths Chapter 7 Integrals solved by Expert Teachers as per NCERT (CBSE) Book guidelines and brought to you by Toppers Bulletin. These Integrals Exercise Questions with Solutions for Class 12 Maths covers all questions of Chapter Integrals Class 12 and help you to revise complete Syllabus and Score More marks as per CBSE Board guidelines from the latest NCERT book for class 12 maths. You can read and download NCERT Book Solution to get a better understanding of all topics and concepts.
7.1 Introduction
7.2 Integration as an Inverse Process of Differentiation
7.2.1 Geometrical interpretation of indefinite integral
7.2.2 Some properties of indefinite integral
7.2.3 Comparison between differentiation and integration
7.3 Methods of Integration
7.3.1 Integration by substitution
7.3.2 Integration using trigonometric identities
7.4 Integrals of Some Particular Functions
7.5 Integration by Partial Fractions
7.6 Integration by Parts
7.6.1 Integral of the type
7.6.2 Integrals of some more types
7.7 Definite Integral
7.7.1 Definite integral as the limit of a sum
7.8 Fundamental Theorem of Calculus
7.8.1 Area function
7.8.2 First fundamental theorem of integral calculus
7.8.3 Second fundamental theorem of integral calculus
7.9 Evaluation of Definite Integrals by Substitution
7.10 Some Properties of Definite Integrals.
Integrals NCERT Solutions – Class 12 Maths
Exercise 7.1 : Solutions of Questions on Page Number : 299
Q1 :sin 2x
Answer :The anti derivative of sin 2x is a function of x whose derivative is sin 2x.
It is known that,
Therefore, the anti derivative of
Q2 :Cos 3x
Answer : The anti derivative of cos 3x is a function of x whose derivative is cos 3x.
It is known that,
Therefore, the anti derivative of .
Q3 :e2x
Answer :The anti derivative of e2x is the function of x whose derivative is e2x.
It is known that,
Therefore, the anti derivative of .
Q4 :
Answer :The anti derivative of is the function of x whose derivative is .
It is known that,
Therefore, the anti derivative of
Q5 :
Answer :
The anti derivative of is the function of x whose derivative is
It is known that,
Therefore, the anti derivative of is .
Q6 :
Answer :
Q7 :
Answer :
Q8 :
Answer :
Q9 :
Answer :
Q10 :
Answer :
Q11 :
Answer :
Q12 :
Answer :
Q13 :
Answer :
On dividing, we obtain
Q14 :
Answer :
Q15 :
Answer :
Q16 :
Answer :
Q17 :
Answer :
Q18 :
Answer :
Q19 :
Answer :
Q20 :
Answer :
Q21 :The anti derivative of equals
(A) (B)
(C) (D)
Answer :
Hence, the correct answer is C.
Q22 :If such that f(2) = 0, then f(x) is
(A) (B)
(C) (D)
Answer :It is given that,
∴Anti derivative of
∴
Also,
Hence, the correct answer is A.
Exercise 7.2 : Solutions of Questions on Page Number : 304
Q1 :
Answer :
Let = t
∴2x dx = dt
Q2 :
Answer :
Let log |x| = t
∴
Q3 :
Answer :
Let 1 + log x = t
∴
Q4 :sin x . sin (cos x)
Answer : sin x â‹… sin (cos x)
Let cos x = t
∴ – sin x dx = dt
Q5 :
Answer :
Let∴ 2adx = dt
Q6 :
Answer :
Let ax + b = t
⇒ adx = dt
Q7 :
Answer :Let
∴ dx = dt
Q8 :
Answer :
Let 1 + 2×2 = t
∴ 4xdx = dt
Q9 :
Answer :
Let
∴ (2x + 1)dx = dt
Q10 :
Answer :
Let
∴
Q11 :
Answer :
Q12 :
Answer :
Let
∴
Q13 :
Answer :
Let
∴ 9×2 dx = dt
Q14 :
Answer :
Let log x = t
∴
Q15 :
Answer :
Let∴ – 8x dx = dt
Q16 :
Answer :
Let∴ 2dx = dt
Q17 :
Answer :
Let∴ 2xdx = dt
Q18 :
Answer :
Let
Q19 :
Answer :
Dividing numerator and denominator by ex, we obtain
Let
∴
Q20 :
Answer :
Let
∴
Q21 :
Answer :
Let 2x – 3 = t
∴ 2dx = dt
Q22 :
Answer :
Let 7 – 4x = t
∴ – 4dx = dt
Q23 :
Answer :
Let
∴
Q24 :
Answer :
Let
∴
Q25 :
Answer :
Let
∴
Q26 :
Answer :
Let
∴
Q27 :
Answer :
Let sin 2x = t
∴
Q28 :
Answer :
Let∴ cos x dx = dt
Q29 :cot x log sin x
Answer :
Let log sin x = t
Q30 :
Answer :
Let 1 + cos x = t
∴ – sin x dx = dt
Q31 :
Answer :
Let 1 + cos x = t
∴ – sin x dx = dt
Q32 :
Answer :
Let sin x + cos x = t ⇒ (cos x – sin x) dx = dt
Q33 :
Answer :
Put cos x – sin x = t ⇒ ( – sin x – cos x) dx = dt
Q34 :
Answer :
Q35 :
Answer :
Let 1 + log x = t
∴
Q36 :
Answer :
Let
∴
Q37 :
Answer :
Let x4 = t
∴ 4x3dx = dt
Let
∴
From (1), we obtain
Q38 :equals
Answer :
Let
∴
Hence, the correct answer is D.
Q39 :equals
Answer :
Let
∴
Hence, the correct answer is D.
Exercise 7.3 : Solutions of Questions on Page Number : 307
Q1 :
Answer :
Q2 :
Answer :
It is known that,
Q3 : cos 2x cos 4x cos 6x
Answer :
It is known that,
Q4 : sin3 (2x + 1)
Answer :
Let
Q5 : sin3 x cos3 x
Answer :
Q6 : sin x sin 2x sin 3x
Answer :
It is known that,
Q7 : sin 4x sin 8x
Answer :
It is known that,
Q8 :
Answer :
Q9 :
Answer :
Q10 : sin4 x
Answer :
Q11 : cos4 2x
Answer :
Q12 :
Answer :
Q13 :
Answer :
Q14 :
Answer :
Q15 :
Answer :
Q16 : tan4x
Answer :
From equation (1), we obtain
Q17 :
Answer :
Q18 :
Answer :
Q19 :
Answer :
Q20 :
Answer :
Q21 : sin-1 (cos x)
Answer :
It is known that,
Substituting in equation (1), we obtain
Q22 :
Answer :
Q23 :is equal to
A. tan x + cot x + C
B. tan x + cosec x + C
C. – tan x + cot x + C
D. tan x + sec x + C
Answer :
Hence, the correct answer is A.
Q24 :equals
A. – cot (exx) + C
B. tan (xex) + C
C. tan (ex) + C
D. cot (ex) + C
Answer :
Let exx = t
Hence, the correct answer is B.
Exercise 7.4 : Solutions of Questions on Page Number : 315
Q1 :
Answer :
Let x3 = t
∴ 3x2 dx = dt
Q2 :
Answer :
Let 2x = t
∴ 2dx = dt
Q3 :
Answer :
Let 2 – x = t
⇒ – dx = dt
Q4 :
Answer :
Let 5x = t
∴ 5dx = dt
Q5 :
Answer :
Q6 :
Answer :
Let x3 = t
∴ 3×2 dx = dt
Q7 :
Answer :
From (1), we obtain
Q8 :
Answer :
Let x3 = t
⇒ 3x2 dx = dt
Q9 :
Answer :
Let tan x = t
∴ sec2x dx = dt
Q10 :
Answer :
Q12 :
Answer :
Q13 :
Answer :
Q14 :
Answer :
Q15 :
Answer :
Q16 :
Answer :
Equating the coefficients of x and constant term on both sides, we obtain
4A = 4 ⇒ A = 1
A + B = 1 ⇒ B = 0
Let 2×2 + x – 3 = t
∴ (4x + 1) dx = dt
Q17 :
Answer :
Equating the coefficients of x and constant term on both sides, we obtain
From (1), we obtain
From equation (2), we obtain
Q18 :
Answer:
Equating the coefficients of x and constant term on both sides, we obtain
Substituting equations (2) and (3) in (1), we obtain
Q19 :
Answer :Answre
Equating the coefficients of x and constant term, we obtain
2A = 6 ⇒ A = 3
– 9A + B = 7 ⇒ B = 34
∴ 6x + 7 = 3 (2x – 9) + 34
Substituting equations (2) and (3) in (1), we obtain
Q20 :
Answer :
Equating the coefficients of x and constant term on both sides, we obtain
Using equations (2) and (3) in (1), we obtain
Q21 :
Answer :
Let x2 + 2x +3 = t
⇒ (2x + 2) dx =dt
Using equations (2) and (3) in (1), we obtain
Q22 :
Answer :
Equating the coefficients of x and constant term on both sides, we obtain
Substituting (2) and (3) in (1), we obtain
Q23 :
Answer :
Equating the coefficients of x and constant term, we obtain
Using equations (2) and (3) in (1), we obtain
Q24 :equals
A. x tan – 1 (x + 1) + C
B. tan – 1 (x + 1) + C
C. (x + 1) tan – 1 x + C
D. tan – 1x + C
Answer :
Hence, the correct answer is B.
Q25 :equals
A.
B.
C.
D.
Answer :
Hence, the correct answer is B.
Exercise 7.5 : Solutions of Questions on Page Number : 322
Q1 :
Answer :
Let
Equating the coefficients of x and constant term, we obtain
A + B = 1
2A + B = 0
On solving, we obtain
A = – 1 and B = 2
Q2 :
Answer :
Let
Equating the coefficients of x and constant term, we obtain
A + B = 0
– 3A + 3B = 1
On solving, we obtain
Q3 :
Answer :
Let
Substituting x = 1, 2, and 3 respectively in equation (1), we obtain
A = 1, B = – 5, and C = 4
Q4 :
Answer :
Let
Substituting x = 1, 2, and 3 respectively in equation (1), we obtain
Q5 :
Answer :
Let
Substituting x = – 1 and – 2 in equation (1),we obtain
A = – 2 and B = 4
Q6 :
Answer :
It can be seen that the given integrand is not a proper fraction.
Therefore, on dividing (1 – x2) by x(1 – 2x), we obtain
Let
Substituting x = 0 and in equation (1), we obtain
A = 2 and B = 3
Substituting in equation (1), we obtain
Q7 :
Answer :
Let
Equating the coefficients of x2, x, and constant term, we obtain
A + C = 0
– A + B = 1
– B + C = 0
On solving these equations, we obtain
From equation (1), we obtain
Q8 :
Answer :
Let
Substituting x = 1, we obtain
Equating the coefficients of x2 and constant term, we obtain
A + C = 0
– 2A + 2B + C = 0
On solving, we obtain
Q9 :
Answer :
Let
Substituting x = 1 in equation (1), we obtain
B = 4
Equating the coefficients of x2 and x, we obtain
A + C = 0
B – 2C = 3
On solving, we obtain
Q10 :
Answer :
Let
Equating the coefficients of x2 and x, we obtain
Q11 :
Answer :
Let
Substituting x = – 1, – 2, and 2 respectively in equation (1), we obtain
Q12 :
Answer :
It can be seen that the given integrand is not a proper fraction.
Therefore, on dividing (x3 + x + 1) by x2 – 1, we obtain
Let
Substituting x = 1 and – 1 in equation (1), we obtain
Q13 :
Answer :
Equating the coefficient of x2, x, and constant term, we obtain
A – B = 0
B – C = 0
A + C = 2
On solving these equations, we obtain
A = 1, B = 1, and C = 1
Q14 :
Answer :
Equating the coefficient of x and constant term, we obtain
A = 3
2A + B = – 1 ⇒ B = – 7
Q15 :
Answer :
Equating the coefficient of x3, x2, x, and constant term, we obtain
On solving these equations, we obtain
Q16 :[Hint: multiply numerator and denominator by xn – 1 and put xn = t]
Answer :
Multiplying numerator and denominator by xn – 1, we obtain
Substituting t = 0, – 1 in equation (1), we obtain
A = 1 and B = – 1
Q17 :[Hint: Put sin x = t]
Answer :
Substituting t = 2 and then t = 1 in equation (1), we obtain
A = 1 and B = – 1
Q18 :
Answer :
Equating the coefficients of x3, x2, x, and constant term, we obtain
A + C = 0
B + D = 4
4A + 3C = 0
4B + 3D = 10
On solving these equations, we obtain
A = 0, B = – 2, C = 0, and D = 6
Q19 :
Answer :
Let x2 = t ⇒ 2x dx = dt
Substituting t = – 3 and t = – 1 in equation (1), we obtain
Q20 :
Answer :
Multiplying numerator and denominator by x3, we obtain
Let x4 = t ⇒ 4x3dx = dt
Substituting t = 0 and 1 in (1), we obtain
A = – 1 and B = 1
Q21 :[Hint: Put ex = t]
Answer :
Let ex = t ⇒ ex dx = dt
Substituting t = 1 and t = 0 in equation (1), we obtain
A = – 1 and B = 1
Q22 :
A.
B.
C.
D.
Answer :
Substituting x = 1 and 2 in (1), we obtain
A = – 1 and B = 2
Hence, the correct answer is B.
Q23 :
A.
B.
C.
D.
Answer :
Equating the coefficients of x2, x, and constant term, we obtain
A + B = 0
C = 0
A = 1
On solving these equations, we obtain
A = 1, B = – 1, and C = 0
Hence, the correct answer is A.
Exercise 7.6 : Solutions of Questions on Page Number : 327
Q1 : x sin x
Answer :
Let I =
Taking x as first function and sin x as second function and integrating by parts, we obtain
Q2 :
Answer :
Let I =
Taking x as first function and sin 3x as second function and integrating by parts, we obtain
Q3 :
Answer :
Let
Taking x2 as first function and ex as second function and integrating by parts, we obtain
Again integrating by parts, we obtain
Q4 : x logx
Answer :
Let
Taking log x as first function and x as second function and integrating by parts, we obtain
Q5 :x log 2x
Answer :
LetTaking log 2x as first function and x as second function and integrating by parts, we obtain
Q6 : x2 log x
Answer :
LetTaking log x as first function and x2 as second function and integrating by parts, we obtain
Q7 :
Answer :
Let
Taking as first function and x as second function and integrating by parts, we obtain
Q8 :
Answer :
Let
Taking as first function and x as second function and integrating by parts, we obtain
Q9 :
Answer :
Let
Taking cos – 1 x as first function and x as second function and integrating by parts, we obtain
Q10 :
Answer :
Let
Taking as first function and 1 as second function and integrating by parts, we obtain
Q11 :
Answer :
Let
Taking as first function and as second function and integrating by parts, we obtain
Q12 :
Answer :
Let
Taking x as first function and sec2x as second function and integrating by parts, we obtain
Q13 :
Answer :
Let
Taking as first function and 1 as second function and integrating by parts, we obtain
Q14 :
Answer :
Taking as first function and x as second function and integrating by parts, we obtain
Q15 :
Answer :
Let
Let I = I1 + I2 … (1)
Where,and
Taking log x as first function and x2 as second function and integrating by parts, we obtain
Taking log x as first function and 1 as second function and integrating by parts, we obtain
Using equations (2) and (3) in (1), we obtain
Q16 :
Answer :
Let
Let
⇒
∴
It is known that,
Q17 :
Answer :
Let
Let
⇒
It is known that,
Q18 :
Answer :
Let⇒
It is known that,
From equation (1), we obtain
Q19 :
Answer :
Also, let ⇒
It is known that,
Q20 :
Answer :
Let
⇒
It is known that,
Q21:
Answer :
Let
Integrating by parts, we obtain
Again integrating by parts, we obtain
Q22 :
Answer :
Let ⇒
= 2θ
⇒
Integrating by parts, we obtain
Q23 :equals
Answer :
Let
Also, let ⇒
Hence, the correct answer is A.
Q24 :equals
Answer :
Let
Also, let ⇒
It is known that,
Hence, the correct answer is B.
Exercise 7.7 : Solutions of Questions on Page Number : 330
Q1 :
Answer :
Q2 :
Answer :
Q3 :
Answer :
Q4 :
Answer :
Q5 :
Answer :
Q6 :
Answer :
Q7 :
Answer :
Q8 :
Answer :
Q9 :
Answer :
Q10 :is equal to
A.
B.
C.
D.
Answer :
Hence, the correct answer is A.
Q11 :is equal to
A.
B.
C.
D.
Answer :
Hence, the correct answer is D.
Exercise 7.8 : Solutions of Questions on Page Number : 334
Q1 :
Answer :
It is known that,
Q2 :
Answer :
It is known that,
Q3 :
Answer :
It is known that,
Q4 :
Answer :
It is known that,
From equations (2) and (3), we obtain
Q5 :
Answer :
It is known that,
Q6 :
Answer :
It is known that,
Exercise 7.9 : Solutions of Questions on Page Number : 338
Q1 :
Answer :
By second fundamental theorem of calculus, we obtain
Q2 :
Answer :
By second fundamental theorem of calculus, we obtain
Q3 :
Answer :
By second fundamental theorem of calculus, we obtain
Q4 :
Answer :
By second fundamental theorem of calculus, we obtain
Q5 :
Answer :
By second fundamental theorem of calculus, we obtain
Q6 :
Answer :
By second fundamental theorem of calculus, we obtain
Q7 :
Answer :
By second fundamental theorem of calculus, we obtain
Q8 :
Answer :
By second fundamental theorem of calculus, we obtain
Q9 :
Answer :
By second fundamental theorem of calculus, we obtain
Q10 :
Answer :
By second fundamental theorem of calculus, we obtain
Q11 :
Answer :
By second fundamental theorem of calculus, we obtain
Q12 :
Answer :
By second fundamental theorem of calculus, we obtain
Q13 :
Answer :
By second fundamental theorem of calculus, we obtain
Q14 :
Answer :
By second fundamental theorem of calculus, we obtain
Q15 :
Answer :
By second fundamental theorem of calculus, we obtain
Q16 :
Answer :
Let
Equating the coefficients of x and constant term, we obtain
A = 10 and B = – 25
Substituting the value of I1 in (1), we obtain
Q17 :
Answer :
By second fundamental theorem of calculus, we obtain
Q18 :
Answer :
By second fundamental theorem of calculus, we obtain
Q19 :
Answer :
By second fundamental theorem of calculus, we obtain
Q20 :
Answer :
By second fundamental theorem of calculus, we obtain
Q21 : equals
A.
B.
C.
D.
Answer :
By second fundamental theorem of calculus, we obtain
Hence, the correct answer is D.
Q22 : equals
A.
B.
C.
D.
Answer :
By second fundamental theorem of calculus, we obtain
Hence, the correct answer is C.
Exercise 7.10 : Solutions of Questions on Page Number : 340
Q1 :
Answer :
When x = 0, t = 1 and when x = 1, t = 2
Q2 :
Answer :
When x = 0, t = 1 and when x = 1, t = 2
Q3 :
Answer :
Also, let
Q4 :
Answer :
Also, let
Q5 :
Answer :
Also, let x = tanθ ⇒ dx = sec2θ dθ
When x = 0, θ = 0 and when x = 1,
Takingθas first function and sec2θ as second function and integrating by parts, we obtain
Q6 :
Answer :
Also, let x = tanθ ⇒ dx = sec2θ dθ
When x = 0, θ = 0 and when x = 1,
Taking θ as first function and sec2θ as second function and integrating by parts, we obtain
Q7 :
Answer :
Let x + 2 = t2 ⇒ dx = 2tdt
When x = 0, and when x = 2, t = 2
Q8 :
Answer :
Let x + 2 = t2 ⇒ dx = 2tdt
When x = 0, and when x = 2, t = 2
Q9 :
Answer :
Let cos x = t ⇒ – sinx dx = dt
When x = 0, t = 1 and when
Q10 :
Answer :
Let cos x = t ⇒ – sinx dx = dt
When x = 0, t = 1 and when
Q11 :
Answer :
Let ⇒ dx = dt
Q12 :
Answer :
Let ⇒ dx = dt
Q13 :
Answer :
Let x + 1 = t ⇒ dx = dt
When x = – 1, t = 0 and when x = 1, t = 2
Q14 :
Answer :
Let x + 1 = t ⇒ dx = dt
When x = – 1, t = 0 and when x = 1, t = 2
Q15 :
Answer :
Let 2x = t ⇒ 2dx = dt
When x = 1, t = 2 and when x = 2, t = 4
Q16 :
Answer :
Let 2x = t ⇒ 2dx = dt
When x = 1, t = 2 and when x = 2, t = 4
Q17 : The value of the integral is
A. 6
B. 0
C. 3
D. 4
Answer :
Let cotθ = t ⇒ – cosec2θ dθ= dt
Hence, the correct answer is A.
Q18 : The value of the integral is
A. 6
B. 0
C. 3
D. 4
Answer :
Let cotθ = t ⇒ – cosec2θ dθ= dt
Hence, the correct answer is A.
Q19 : If
A. cos x + x sin x
B. x sinx
C. x cos x
D. sin x + x cos x
Answer :
Integrating by parts, we obtain
Hence, the correct answer is B.
Q20 : If
A. cos x + x sin x
B. x sinx
C. x cos x
D. sin x + x cos x
Answer :
Integrating by parts, we obtain
Hence, the correct answer is B.
Exercise 7.11 : Solutions of Questions on Page Number : 347
Q1 :
Answer :
Adding (1) and (2), we obtain
Q2 :
Answer :
Adding (1) and (2), we obtain
Q3 :
Answer :
Adding (1) and (2), we obtain
Q4 :
Answer :
Adding (1) and (2), we obtain
Q5 :Answer :
Adding (1) and (2), we obtain
Q6 :
Answer :
Adding (1) and (2), we obtain
Q7 :Answer :
Adding (1) and (2), we obtain
Q8 : Answer :
Q9 :
Answer :
Q10 :
Answer :
Adding (1) and (2), We obtain
Q11 : Answer :
As sin2(-x)=(sin(-x)) = (-sinx)2= sin2x, therefore, sin2x is an even function.
It is known that if f(x) is an even function,then
Q12 :
Answer :
Q13 :
Answer :
As sin7(-x)=(sin(-x))7=(-sinx)7=-sin7x,therefore,sin2x is an even function.
It is known that if f(x) is an even function,then
Q14 :
Answer :
It is known that,
Q15 :
Answer :
Adding (1) and (2), we obtain,
Q16 :
Answer :
Adding (1) and (2), we obtain,
sin(Π-x)=sinx
Adding (4) and (5), we obtain,
Q17 :
Answer :
It is known that,
Adding (1) and (2),we obtain,
Q18 :
Answer :
It can be seen that,(x-a) ≤ 0 when 0 ≤ x ≤1 and(x-1) ≥0 when 1 ≤ x ≤ 4.
Q19 : Show that if f and g defined asand
Answer :
Adding (1) and (2), we obtain
Q20 : The value of
A.0
B.2
C.Π
D.
Answer :
It is known that if f(x) is an even function,then
and f(x) is an odd function,then
Hence,the correct answer is C.
Q21 : The value of
A. 2
B. C. 0
D. -2
Answer :
Adding (1) and (2),we obtain,
Hence the correct answer is C.
Exercise Miscellaneous : Solutions of Questions on Page Number : 352
Q1 :
Answer :
Equating the coefficients of x2, x, and constant term, we obtain
– A + B – C = 0
B + C = 0
A = 1
On solving these equations, we obtain
From equation (1), we obtain
Q2 :
Answer :
Q3 :
[Hint: Put]
Answer :
Q4 :
Answer :
Q5 :
Answer :
On dividing, we obtain
Q6 :
Answer :
Equating the coefficients of x2, x, and constant term, we obtain
A + B = 0
B + C = 5
9A + C = 0
On solving these equations, we obtain
From equation (1), we obtain
Q7 :
Answer :
Let x – a = t ⇒ dx = dt
Q8 :
Answer :
Q9 :
Answer :
Let sin x = t ⇒ cos x dx = dt
Q10 :
Answer :
Q11 :
Answer :
Q12 :
Answer :
Let x4 =t ⇒ 4x3 dx = dt
Q13 :
Answer :
Let ex = t ⇒ ex dx = dt
Q14 :
Answer :
Equating the coefficients of x3, x2, x, and constant term, we obtain
A + C = 0
B + D = 0
4A + C = 0
4B + D = 1
On solving these equations, we obtain
From equation (1), we obtain
Q15 :
Answer :
= cos3 x × sin x
Let cos x = t ⇒ – sin x dx =dt
Q16 :
Answer :
Q17 :
Answer :
Q18 :
Answer :
Q19 :
Answer :
Q20 :
Answer :
Q21 :
Answer :
Q22 :
Answer :
Equating the coefficients of x2, x,and constant term, we obtain
A + C = 1
3A + B + 2C = 1
2A + 2B + C = 1
On solving these equations, we obtain
A = – 2, B = 1, and C = 3
From equation (1), we obtain
Q23 :
Answer :
Q24 :
Answer :
Integrating by parts, we obtain
Q25 :
Answer :
Q26 :
Answer :
When x = 0, t = 0 and
Q27 :
Answer :
When and when
Q28 :
Answer :
When and when
As ,
therefore, is an even function.
It is known that if f(x) is an even function, then
Q29 :
Answer :
Q30 :
Answer :
Q31 :
Answer :
From equation (1), we obtain
Q32 :
Answer :
Adding (1) and (2), we obtain
Q33 :
Answer :
a
From equation (1),(2),(3) and (4), we obtain
Q34 :
Answer :
Equating the coefficients of x2, x, and constant term, we obtain
A + C = 0
A + B = 0
B = 1
On solving these equations, we obtain
A = – 1, C = 1, and B = 1
Hence, the given result is proved.
Q35 : Answer :
Integrating by parts, we obtain
Hence, the given result is proved.
Q36 :
Answer :
Therefore, f (x) is an odd function.
It is known that if f(x) is an odd function, then
Hence, the given result is proved.
Q37 :
Answer :
Hence, the given result is proved.
Q38 :Answer :
Hence, the given result is proved.
Q39 :
Answer :
Integrating by parts, we obtain
Let 1 – x2 = t ⇒ – 2x dx = dt
Hence, the given result is proved.
Q40 :
Evaluate as a limit of a sum.
Answer :
It is known that,
Q41 :
is equal to
A.
B.
C.
D.
Answer :
Hence, the correct answer is A.
Q42 :
is equal to
A.
B.
C.
D.
Answer :
Hence, the correct answer is B.
Q43 : If then is equal to
A.
B.
C.
D.
Answer :
Hence, the cor
Correct answer is D.
Q44 :
The value of is
A. 1
B. 0
C. – 1
D.
Answer :
Adding (1) and (2), we obtain
Hence, the correct answer is B.