Let X and Y be any sets and let F be any one-to-one (injective) function from...

Question

Question

Let X and Y be any sets and let F be any one-to-one (injective) function from X to Y . Prove that for every subset A ⊂ X:

(a) (10 points) A ⊂ F^(−1) (F(A)).

(b) (10 points) F ^(−1) (F(A)) ⊂ A

Answer 1

Answer #1

Given Given that, F: XY is injective and acx. (a) Hence (b) het het XEA . F(a) FF (A) - 1 FCC (A)). A CF (FW). xe F( (A)) a

Answer 2

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