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If A, B are square matrices of same order and B is a skew-symmetric matrix, show that A′BA is skew-symmetric.

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Question

If A, B are square matrices of same order and B is a skew-symmetric matrix, show that A′BA is skew-symmetric.

Sum
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Solution

Given that B is a skew-symmetric matrix

∴ B' = – B

Let P = A'BA

⇒ P' = (A'BA)'

= A'B'(A')'  .....[(AB)' = B'A']

= A'(– B) A

= – A'BA

= – P

So P' = – P

Hence, A'BA is a skew-symmetric matrix.

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Chapter 3: Matrices - Exercise [Page 58]

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NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 3 Matrices
Exercise | Q 48 | Page 58

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