Question

Prove that A union (B - A) = A union B

Answer 1

Suppose that u have a set of A=(1234) and B=(357) thus when u do AU(B-A) no number is minus from B because it does not have a single number that matches to A so u cant minus anything. So u have to make union of all numbers such AU(B-A)=(123457) which is equal to AUB=(123457) Hope u understand