Question

The trace of the matrix \[A = \begin{bmatrix}1 & - 5 & 7 \\ 0 & 7 & 9 \\ 11 & 8 & 9\end{bmatrix}\], is

Options

• 17

• 25

• 3

• 12

Answer 1

 17 

The trace of a matrix is the sum of the diagonal elements.

\[\therefore\] Tr

 \[\left( A \right)\]   = 1 + 7 + 9 = 17