Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Relations and Functions

Question:

Find the range of the function $f(x)=\sin^{-1}((1+e^x)^{-1})$.

Options:

$(-\frac{π}{2},\frac{π}{2})$

$(0,\frac{π}{2})$

$(-\frac{π}{2},1)$

$(\frac{π}{2},\frac{π}{2})$

Correct Answer:

$(0,\frac{π}{2})$

Explanation:

$e^x∈(0,∞)$

$e^x+1∈(1,∞)$

$(e^x+1)^{-1}∈(0,1)$

so $\sin^{-1}(e^x+1)^{-1}∈(0,\frac{π}{2})$