Question

If a function from $R\to R$ such that $f\left(x\right)=x^2\forall xϵR$ then show that f is not one-one.

Answer 1

$f\left(x\right)=x^2$

$f:R\to R$

ref. image I

$f\left(0\right)=0$

For one - one there will be two values Ref. image I

$f\left(x\right):R\to R$

$\lambda <0\in$ Codomain

$\lambda <0$ is not present is range

$\therefore$ It is not one one function.