# Trace of a matrix equals sum of its determinants?

1. ### samspotting

86
If a matrix is diagonalizable, how does its trace equal the sum of its eigenvalues?

I can't find a proof for this anywhere.

2. ### Hurkyl

16,089
Staff Emeritus
What is the trace of a diagonal matrix? What are the algebraic properties of trace?

3. ### samspotting

86
Ah I see, the trace is similarity invariant. thanks