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If A is a skew-symmetric matrix, then A2 is a ______.

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Question

If A is a skew-symmetric matrix, then A2 is a ______.

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Solution

If A is a skew-symmetric matrix, then A2 is a symmetric matrix.

Explanation:

Given A is skew-symmetric matrix.

∴ A' = –A

∴ (A2)' = (A')2

= (–A)2

= A2

So, A2 is a symmetric martix.

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Chapter 3: Matrices - Exercise [Page 62]

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NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 3 Matrices
Exercise | Q 75 | Page 62

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