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

Sum

Solution

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

L.H.S. kA = `"k"[(0, -1, 2),(4, 3, -4)]`

= `[(0, -"k", 2"k"),(4"k", 3"k", -4"k")]`

(kA)' = `[(0, 4"k"),(-"k", 3"k"),(2"k", -"k")]`

R.H.S. kA' = `"k"[(0, -1, 2),(4, 3, -4)]^'`

= `"k"[(0, 4),(-1, 3),(2, -4)]`

= `[(0, 4"k"),(-"k", 3"k"),(2"k", -4"k")]`

Hence, L.H.S. = R.H.S.

(kA)' = (kA') is verified.

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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. (iii) | Page 56

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