(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

If p is a prime greater than 3, then p leaves a remainder of 1 or 5 when divided by 6.

2. Relevant equations

I have been given the definition of composite which is an integer a is composite if there exist integers b and c such that a=bc where both b>1, c>1

3. My attempt

Let P be a prime number greater than 3

P=6q+r 1<=r<=5 by the division algorithm

This is where I get lost. I'm not even sure if line two is the way to approach this proof.

SHould I do separate cases such as

CaseI: r=1 so p=6q+1 ?

I dont think so because that would not be proving anything but rather it would be a retelling of what I need to prove.

Thanks for your time and help

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# Homework Help: Prime Number Proof

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