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Question
Choose the correct alternative.
If a 3 x 3 matrix B has it inverse equal to B, thenB2 = _______
Options
`[(0, 1, 1),(0, 1, 0),(1, 0, 1)]`
`[(1, 1, 1),(1, 1, 1),(1, 0, 1)]`
`[(1, 0, 1),(0, 1, 0),(0, 0, 0)]`
`[(1, 0, 0),(0, 1, 0),(0, 0, 1)]`
Solution
B–1 = B
∴ B–1B = B.B
∴ B2 = I = `[(1, 0, 0),(0, 1, 0),(0, 0, 1)]`.
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