For each of the following determine whether it is valid or i

For each of the following, determine whether it is valid or invalid. If valid then give a proof. If invalid then give a counter example.

(a) A C and B C A B C

(b) (B C) A (C A) (B A) =

(c) (A B) (A B) = A B =

(d) (A × C) (B × D) = (A B) × (C D)

*Please show work if needed*

Solution

a) true

b) true

c)false

d)true