What is the trace of the 3x3 matrix with diagonal entries 5, -2, and 8?
Answer and explanation
Correct answer: D. 11
- Step 1: The trace of a square matrix is the sum of its main diagonal elements. Step 2. Trace = 5 + (-2) + 8 = 11. Answer: 11. Why not the others: 15 ignores the negative sign; 1 calculates 5 - 2 - 2; -80 is the product of diagonal elements.
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