Question
Question: \(\tan ^ { - 1 } \frac { 1 } { \sqrt { x ^ { 2 } - 1 } } =\)...
tan−1x2−11=
A
2π+cosec−1x
B
2π+sec−1x
C
cosec−1x
D
sec−1x
Answer
cosec−1x
Explanation
Solution
tan−1x2−11=tan−1cosec2θ−11
(Putting x=cosecθ)
=tan−1cotθ1=θ=cosec−1x.