Question:
Trace the matrix \[ \begin{bmatrix} 3 & 2 & 1 & 4 \\ 5 & 7 & 8 & 1 \\ 2 & 4 & 6 & 7 \\ 9 & 6 & 4 & 2 \end{bmatrix} \] (answer in integer).
Trace the matrix \[ \begin{bmatrix} 3 & 2 & 1 & 4 \\ 5 & 7 & 8 & 1 \\ 2 & 4 & 6 & 7 \\ 9 & 6 & 4 & 2 \end{bmatrix} \] (answer in integer).
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Trace = sum of diagonal elements only — nothing else.
Updated On: Dec 22, 2025
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Correct Answer: 18
Solution and Explanation
Trace is the sum of diagonal terms:
\[
3 + 7 + 6 + 2 = 18
\]
\[
\boxed{18}
\]
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