Alright, having problems with this question too. It seems to be the same type of number theory problem, which is the problem.(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

Prove "The square of any integer has the form 4k or 4k+1 for some integer k.

2. Relevant equations

definition of even= 2k

definition of odd= 2k+1

3. The attempt at a solution

Basically I have: Case 1. 2k(2k) = 4k

Case 2. 2k+1(2k+1) = 4k^{2}+4k+1 = 4k+1(k+1)

Not sure if it's correct. Do I need to use different indices? I feel I am missing something. Thanks for any help!

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# Homework Help: Simple Number Theory Proof, Again!

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