Matrices · Class 12 · CBSE · Science Mathematics
Find the inverse of the matrix A = [[2, 1], [1, 1]].
Practice question from Matrices (Class 12 · CBSE · Science Mathematics), with the correct answer and a step-by-step solution.
medium · MCQ · Q-047251
Find the inverse of the matrix A = [[2, 1], [1, 1]].
- A.[[1, -1], [-1, 2]]Correct answer
- B.[[1, 1], [1, 2]]
- C.[[2, -1], [-1, 1]]
- D.[[1, -2], [-1, 2]]
Solution
The determinant of A is 2(1) − 1(1) = 1. Hence A⁻¹ = 1/det(A) [[1, −1], [−1, 2]] = [[1, −1], [−1, 2]].
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