Prove that if g and f are 1-1, then so is g o f. And prove that if g and f are onto, then so is g o f.

Printable View

- Apr 17th 2011, 11:22 AMandirc5192Compositions
Prove that if g and f are 1-1, then so is g o f. And prove that if g and f are onto, then so is g o f.

- Apr 17th 2011, 11:27 AMPlato
- Apr 17th 2011, 11:51 AMandirc5192
Oh geez yeah sorry about that. I understand that, by definition, g: A-->B is one to one if and only if w,x are in A where w is not equal to x and g(w)=g(x) implies that w=x, and the same thing for f:C-->D where y,z are in C. However i'm not sure how to connect the two through a composition.

- Apr 17th 2011, 12:44 PMPlato
If and what does mean?

If (y)= show