What is the determinant of the 3x3 matrix with rows [1, 2, 3], [0, 4, 5], [0, 0, 6]?
Answer and explanation
Correct answer: B. 24
- Step 1: The matrix is upper triangular. Step 2. The determinant of an upper (or lower) triangular matrix is simply the product of its main diagonal entries. Step 3. det(A) = 1 4 6 = 24. Answer: 24. Why not the others: 0 is for singular matrices; 12 neglects the factor of 2.
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