CUET Preparation Today
If $f:[3, \infty) \rightarrow$ A defined by $f(x)=x^2$ is an onto function, then $A$ is : |
$R$ $[5, \infty)$ $[6, \infty)$ $[9, \infty)$ |
$[9, \infty)$ |
f : [3, ∞) → A f is onto so every image in A must have atleast one pre-image $f(x) = x^2$ for boundary conditions $f(3) = 9$ $\lim\limits_{x \rightarrow \infty} f(x) \rightarrow \infty$ so A = [9, ∞) |
