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

1.Prove that if A is a real matrix then At A is diagonalisable.

2. Given a known 3*3 matrix A, Calculate the maximum and minimum values of ||Ax|| on the sphere ||x|| = 1.

2. Relevant equations

3. The attempt at a solution

For the first problem, I'm thinking of proving that AtA is symmetric, but I'm not sure which properties to use.

For the second one, is X a 3*n matrix? Do I need to discuss n?

Any help is greatly appreciated!

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# Homework Help: Diagonalisability problem and others

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