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blue_leaf77

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## Homework Statement

This question is taken from Linear Algebra Done Wrong by Treil. Question 7.5 of chapter 1 says this:

What is the smallest subspace of the space of 4 4 matrices which contains all upper triangular matrices (a

_{j,k}= 0 for all j > k), and all symmetric matrices (A = A

^{T})? What is the largest subspace contained in both of those subspaces?

## Homework Equations

May be these a

_{j,k}= 0 for all j > k and A = A

^{T}

## The Attempt at a Solution

I'm just not sure with my answer because it sounds too short for such an elaborate question.

1st answer: the zero matrix, the one with all-zero entries.

2nd answer: the two subspaces themself.