हिंदी

If A and B are symmetric matrices, prove that AB – BA is a skew symmetric matrix.

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प्रश्न

If A and B are symmetric matrices, prove that AB – BA is a skew symmetric matrix.

प्रमेय
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उत्तर

If A and B are symmetric matrices.

∴ A’ = A and B’ = B

(AB – BA) = (AB)’ – (BA)’   ...[∵ (X – Y) = X’ – Y’]

= B’A’ – A’B’   ...[∵ (XY) = Y’X’]

= BA – AB   ...[∵ B’ = B, A’ = A]

= –(AB – BA)

∴ AB – BA is a skew symmetric matrix.

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अध्याय 3: Matrices - Miscellaneous Exercise on Chapter 3 [पृष्ठ ७२]

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एनसीईआरटी Mathematics Part 1 and 2 [English] Class 12
अध्याय 3 Matrices
Miscellaneous Exercise on Chapter 3 | Q 1. | पृष्ठ ७२

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