(adsbygoogle = window.adsbygoogle || []).push({}); Biconditional statements with "Or"

If I have a biconditional statement like this: Let p be an integer other than 0, -1, +1. Prove that p is prime if and only if for each a that exists inZeither (a, p) =1 or p|a.

I know that when you have a biconditional, you have to prove the statement both ways. However, when you solve it the other way, do you have to switch it to an "and," or do you have to do three proofs, one forward, and two backward (One for each case)? I have a homework problem where I have to prove this statement, and going forward is easy but to prove it the other way around, I feel like I need both of those statements to actually prove it.

I'm sorry if this is the wrong place to put it!

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Biconditional statements with Or

**Physics Forums | Science Articles, Homework Help, Discussion**