Trace

The trace of a matrix is the sum of its diagonal components. For example, if the diagonal of a 3x3 matrix has entries 1,2,3, then the trace of that matrix is 1+2+3=6.

Determinant

The determinant of a matrix is sometimes tricky to compute. For a 2x2 matrix with first row (a, b) and second row (c, d), the determinant is the quantity ad-bc. For a 3x3 matrix (or large matrices), you can compute the determinant by something called expansion by minors. See any linear algebra book for a multitude of ways to compute determinants.

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Frederick J. Wicklin <fjw@geom.umn.edu>

Last modified: Mon Nov 21 10:46:15 1994