Explain, in one or two sentences, why the function does not have an inverse on , but…

MATHEMATICS · Subjective · CBSE · Mathematics · Relations and Functions · Relations and Functions

Problem

Explain, in one or two sentences, why the function

f:\mathbb{R}\to\mathbb{R},\; f(x)=x^{2}

does not have an inverse on

\mathbb{R}

, but does have an inverse when its domain is restricted to

[0,\infty)