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If A is skew-symmetric, then kA is a ______. (k is any scalar)

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Question

If A is skew-symmetric, then kA is a ______. (k is any scalar)

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Solution

If A is skew-symmetric, then kA is a skew-symmetric matrix. (k is any scalar)

Explanation:

Given A is skew-symmetric matrix

∴ A' = –A

∴ (kA)' = kA'

= k(–A)

= – kA

∴ (kA) is also skew-symmetric matrix.

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Chapter 3: Matrices - Exercise [Page 63]

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NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 3 Matrices
Exercise | Q 77 | Page 63

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