Question

how do you find the interval notation from the domain and range?

Answer 1

interval notation is just a way of writing all the possible values of x and y, so if you know exactly what each are then you can write the notation.

Answer 2

do you just pick out a random number from your outputs?!

Answer 3

no... for example... the graph of y=x^2.... the interval notation for the
domain = All reals
range = y>=0

Answer 4

if you had a specific function I could give you what the interval notation is.