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If A is a square matrix such that A2 = A, find the value of 7A – (I + A)3 - Mathematics

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प्रश्न

If A is a square matrix such that A2 = A, find the value of 7A – (I + A)3

बेरीज

उत्तर

Given A2 = A

So 7A – (I + A)3 

= 7A – (I + 3A + 3A2 + A3)

= 7A – I – 3A – 3 A2 – A3

Given A2 = A

7A – I – 3A – 3A – A3

= – I + A – A3

= – I + A – (A2 × A)

= – I + A – (A × A)

= – I + A – A2

= – I + A – A = -I

So the value of 7A – (I + A)3 = – I.

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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 7: Matrices and Determinants - Exercise 7.1 [पृष्ठ १८]

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सामाचीर कलवी Mathematics - Volume 1 and 2 [English] Class 11 TN Board
पाठ 7 Matrices and Determinants
Exercise 7.1 | Q 12 | पृष्ठ १८

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