functions or not and surjective ,injective.

Question

A2:={(x,y)∈R×R:x=y^3} I need to figure out whether it's a function or not and if it's I need to investigate if it's surjective or/and injective .

I know ,that functions that give two outputs for a single input are not functions and we don't call them functions.

and this is a function because it gives us one input for a single output.

However how to know whether it's injective or surjective i just need a hint or example

Answer 1

Injective means one-to-one: that is Every element in the domain is mapped to ONE and

only one element in the range AND VICE VERSA;

You can use the horizontal line test

y=x and y=x^3 are one to one

Surjective means ONTO: that is ALL of the domain is used