Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Inverse Trigonometric Functions

Question:

The set of values of x for which $tan^{-1}\frac{x}{\sqrt{1-x^2}}= sin^{-1} x $ holds , is 

Options:

R

(-1,1)

[0, 1]

[-1, 0]

Correct Answer:

(-1,1)

Explanation:

We observe that RHS is defined for all x ∈ [-1,1]

whereas LHS is meaningful for -1 < x < 1.

Also, for x ∈(-1, 1), we have

$tan^{-1}\left(\frac{x}{\sqrt{1-x^2}}\right)$

$=tan^{-1}\left(\frac{sin \theta }{\cos\theta }\right)$, where x = sin θ

$= θ = sin^{-1} x $