The Trace

The trace of a matrix is simply the sum of the entries on its main diagonal.

The following are clear from the definition.

a. Trace(A+B)=Trace(A)+Trace(B)

b. Trace(Transpose[A])=Trace(A)

Mathematica has no command to compute the trace of a matrix. It does have a command Trace, but it has an entirely different meaning.

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