Question

A function f: [1, ∞) → [0, ∞) is defined as f(x) = 2x(x - 1). Find f-1(x).

Answer 1

⇒ f is strictly increasing function.

⇒ f is a one one function.

Also, Rt = [1, ∞)

⇒ Rf = [1, ∞) = co-domain

⇒ f is onto function

Thus, f is a bijective function.