# Matrix Theory: Linear transformations and Basis vectors

### Symmetric Matrices

A symmetric matrix looks like this:

$A= \left( \begin{array}{cccc} a & d & n & w \\ d & b & h & e \\ n & h & c & i \\ w & e & i & d \end{array} \right)\$

Notice how the values are reflected across the diagonal a-b-c-d; this holds true for any symmetric matrix.