Let a, b, c e Z. show that ca & cb if and only if c (a, b).

Please help me to write this as a proof.  Let n be an integer. If n is the sum of three consecutive integers, then 3 | n

1. Provide a Boolean Expression to simplify. This expression should involve an overbar over the entire expression. Present TWO different simplification proofs. The first: apply DeMorgan's law as the first step, the second: simplify under the bar first.

What is the modulus and argument of -3. Select all that apply