Recent content by Piffo

If I want to prove that a non specified function f(x) that maps x -->x' is onto could I show that f(x) is one to one and that f(x')^-1 (the inverse function) is also one to one?? Would that be a valid justification to say that thus f(x) must be onto? More specifically I am looking to prove...

Homework Statement Prove that A intersection B is a subset of A union B without using Venn diagrams Homework Equations No relevant equations really The Attempt at a Solution What i am thinking is this: A union B = A+B- A intersection B shows the intersection is within the...