Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Relations and Functions

Question:

Which of the following functions is onto ?

Options:

$f: R→R, f(x) = x^2 $

$f: R→R, f(x) = x^2 +1$

$f: R→R, f(x) = x^2-1 $

$f: R→R, f(x) = 2x+1 $

Correct Answer:

$f: R→R, f(x) = 2x+1 $

Explanation:

The correct answer is Option () → $f: R→R, f(x) = 2x+1$

$\frac{y-1}{2}=x⇒f^{-1}x=\frac{x-1}{2}$

for every $y∈R$

atleast one $x∈R$ exists

⇒ it is onto function