Inverse of function f exists if and only if f is:
- Even
- Continuous
- Bijective (one-one AND onto)
- Linear
Show answer and solution
Correct answer: C. Bijective (one-one AND onto)
f⁻¹ exists iff f is bijection.
We have (f⁻¹ ∘ f)(x) = x.
So (f⁻¹ ∘ f)(x) = (f ∘ f⁻¹)(y).
e.g., f(x) = x³ is bijective; f⁻¹(y) = y^(1/3). f(x) = x² is not.