Thread: Help with composition proof

I am in discrete structures and have to solve this proof and have been having a fairly difficult time with it, probably easy but math was never my strong suit.

If f: A--->B is a bijection and g: B--->C is injective, prove that g o f is injective.

Originally Posted by Dax

I am in discrete structures and have to solve this proof and have been having a fairly difficult time with it, probably easy but math was never my strong suit.
If f: A--->B is a bijection and g: B--->C is injective, prove that g o f is injective.

Start with .
Does that mean ? WHY?
Finish.