Edit: Sorry, I figured this out shortly after posting. It's a simple problem but I hadn't used matrix equations before.(adsbygoogle = window.adsbygoogle || []).push({});

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

If A, B, and C are all square matrices of the same size, show that AB commutes with C if A and B both commute with C.

2. Relevant equations

Formula for matrix multiplication

3. The attempt at a solution

All I know is

AC = CA

BC = CB

A, B, and C are square matrices of the same size

I want to prove that (AB)(C) = (C)(AB).

But I am not sure how to do this, or even how to get started.

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# Help with a simple matrix proof

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