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If A = B[1-253],B=[1-34-7] , then find the matrix A − 2B + 6I, where I is the unit matrix of order 2. - Mathematics and Statistics

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Question

If A = `[(1, -2),(5, 3)], "B" = [(1, -3),(4, -7)]` , then find the matrix A − 2B + 6I, where I is the unit matrix of order 2.

Sum

Solution

A – 2B + 6I = `[(1, -2),(5, 3)] -2[(1, -3),(4, -7)] + 6[(1, 0),(0, 1)]`

= `[(1, -2),(5, 3)] - [(2, -6),(8, -14)] + [(6, 0),(0, 6)]`

= `[(1 - 2 + 6, -2 + 6 + 0),(5 - 8 + 0,  3+ 14 + 6)]`

= `[(5, 4),(-3, 23)]`

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Chapter 2: Matrices - Exercise 2.2 [Page 46]

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