NCERT Solutions for Class 12 Maths Chapter 2 – Inverse Trigonometric Functions Miscellaneous Exercise
Page No 51:
Question 1:
Find the value of 

Answer:
We know that cos−1 (cos x) = x if
, which is the principal value branch of cos −1x.

Here,

Now,
can be written as:


Question 2:
Find the value of 

Answer:
We know that tan−1 (tan x) = x if
, which is the principal value branch of tan −1x.

Here,

Now,



Question 3:
Prove 

Answer:

Now, we have:

Question 4:
Prove 

Answer:

Now, we have:

Question 5:
Prove 

Answer:

Now, we will prove that:

Question 6:
Prove 

Answer:

Now, we have:

Question 7:
Prove 

Answer:

Using (1) and (2), we have

Question 8:
Prove 

Answer:

Page No 52:
Question 9:
Prove 

Answer:

Question 10:
Prove 

Answer:

Question 11:
Prove
[Hint: putx = cos 2θ]

Answer:

Question 12:
Prove 

Answer:

Question 13:
Solve

Answer:


Question 14:
Solve

Answer:

Question 15:
Solve
is equal to

(A)
(B)
(C)
(D) 




Answer:
Let tan−1 x = y. Then, 


The correct answer is D.
Question 16:
Solve
, then x is equal to

(A)
(B)
(C) 0 (D) 



Answer:

Therefore, from equation (1), we have

Put x = sin y. Then, we have:

But, when
, it can be observed that:



Thus, x = 0.
Hence, the correct answer is C.
Question 17:
Solve
is equal to

(A)
(B).
(C)
(D) 




Answer:

Hence, the correct answer is C.