What is the inverse of the matrix [[2, 1], [3, 2]]?
Correct answer: B. [[2, -1], [-3, 1]]
- A. [[2, -1], [-3, 2]]
- B. [[2, -1], [-3, 1]]
- C. [[1, -1], [-3, 2]]
- D. [[2, 1], [3, 2]]
Explanation
The determinant is (2 × 2) - (1 × 3) = 1. Interchanging the diagonal entries and changing the signs of the other entries gives [[2, -1], [-3, 2]], but the listed inverse must be checked carefully. Multiplication shows the correct inverse is [[2, -1], [-3, 2]], so option a is correct.
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