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If A = [0-1243-4] and B = [401326], then verify that: (A′)′ = A - Mathematics

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Question

If A = `[(0, -1, 2),(4, 3, -4)]` and B = `[(4, 0),(1, 3),(2, 6)]`, then verify that: (A′)′ = A

Sum

Solution

Given that: A = `[(0, -1, 2),(4, 3, -4)]`, B = `[(4, 0),(1, 3),(2, 6)]`

A' = `[(0, -1, 2),(4, 3, -4)]_(2 xx 3)^'`

= `[(0, 4),(-1, 3),(2, -4)]_(3 xx 2)`

(A')' = `[(0, 4),(-1, 3),(2, -4)]_(3 xx 2)^'`

= `[(0, -1, 2),(4, 3, -4)]_(2 xx 3)`

= A

Hence, (A')' = A

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Chapter 3: Matrices - Exercise [Page 56]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 3 Matrices
Exercise | Q 27. (i) | Page 56

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