Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Relations and Functions

Question:

Which of the following functions from f : A → A are invertible, where A = [–1, 1]

Options:

$f(x)=\frac{x}{2}$

$g(x)=\sin \left(\frac{\pi x}{2}\right)$

h(x) = |x|

$k(x)=x^2$

Correct Answer:

$g(x)=\sin \left(\frac{\pi x}{2}\right)$

Explanation:

$g(x)=\sin \left(\frac{\pi x}{2}\right)$ is both one–one and onto.

Hence (2) is the correct answer.