If adj(A) = [0-2062-6-306], find A–1 - Mathematics

Question

If adj(A) = `[(0, -2, 0),(6, 2, -6),(-3, 0, 6)]`, find A^–1

Sum

Solution

adj(A) = `[(0, -2, 0),(6, 2, -6),(-3, 0, 6)]`

∴ |adj A| = `[(0, -2, 0),(6, 2, -6),(-3, 0, 6)]`

Expanding along R₁ –(– 2)[36 – 18]

= 2(18)

= 36

A^–1 = `+- 1/sqrt(|"adj A"|)`

adj A = `+- 1/sqrt(36) [(0, -2, 0),(6, 2, -6),(-3, 0, 6)]`

= `+- 1/6 [(0, -2, 0),(6, 2, -6),(-3, 0, 6)]`

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Inverse of a Non-singular Square Matrix

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Chapter 1: Applications of Matrices and Determinants - Exercise 1.1 [Page 16]

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Samacheer Kalvi Mathematics - Volume 1 and 2 [English] Class 12 TN Board

Chapter 1 Applications of Matrices and Determinants
Exercise 1.1 | Q 9 | Page 16

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