Determinants · Class 12 · CBSE · Science Mathematics
Let A = [2 1; 5 3]. Which of the following is A⁻¹?
Practice question from Determinants (Class 12 · CBSE · Science Mathematics), with the correct answer and a step-by-step solution.
hard · MCQ · Q-E57E51
Let A = [2 1; 5 3]. Which of the following is A⁻¹?
- A.[3 −1; −5 2]Correct answer
- B.[2 −1; −5 3]
- C.[3 1; 5 2]
- D.[−3 1; 5 −2]
Solution
Here, |A| = 2 × 3 − 1 × 5 = 1. Therefore, A⁻¹ = (1/|A|)[3 −1; −5 2] = [3 −1; −5 2].
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