Find the determinant of the diagonal matrix .

Answer and explanation

Correct answer: D. 8

  1. Step 1: For a diagonal matrix , all off-diagonal entries are zero, so its determinant equals the product of its diagonal elements: .
  2. Step 2: Identify the diagonal entries , , and : .
  3. Step 3: Multiply the diagonal values: .
Answer
8.
Why not the others: The remaining values (9, 6, 7) result from evaluating the determinant instead of the trace, adding off-diagonal entries, or sign errors.

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