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Show that if A and B are square matrices such that AB = BA, then (A + B)2 = A2 + 2AB + B2. - Mathematics

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प्रश्न

Show that if A and B are square matrices such that AB = BA, then (A + B)2 = A2 + 2AB + B2.

योग

उत्तर

Given, A and B are square matrices such that AB = BA.

So, (A + B)2 = (A + B) · (A + B)

= A2 + AB + BA + B2

= A2 + AB + AB + B2  ......[Since, AB = BA]

= A+ 2AB + B2 

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अध्याय 3: Matrices - Exercise [पृष्ठ ५६]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
अध्याय 3 Matrices
Exercise | Q 31 | पृष्ठ ५६

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