Question

If it says "proves that f∪g : (A∪B)->B". Is it asking to prove the so called "f∪g" relation is a function from (A∪B) to C?

Answer 1

Where did C come from?

Answer 2

A function is a relation which is a set of pairs.

Answer 3

Since relations are sets, they have unions

Answer 4

However, I don't think functions would be closed under unions, i.e. you might get a relation that isn't a function when you take the union.

Answer 5

oh sorry. it's "proves that f∪g : (A∪B)->C" and A and B are disjoint. I'm not asking for how to prove it. I'm just asking what the question is asking me to do.