I'm asked to multiply trace matrices, and then subtract them. I'm not sure the order I need to do the questions in. Can somebody help me here?
tr(BA)-tr(B)tr(A)
Where A=
3 -2 7
6 5 4
0 4 9
and B=
6 -2 4
0 1 3
7 7 5
Multiply BA using the definition. Once you do that to find tr(BA) just add up the ends in the diagnol. Likewise tr(B),tr(A) is the sum in the diagnols.