Tamil Nadu Board of Secondary EducationHSC Arts Class 12

Find the inverse (if it exists) of the following: [-241-3] - Mathematics

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Sum

Find the inverse (if it exists) of the following:

`[(-2, 4),(1, -3)]`

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Solution

`[(-2, 4),(1, -3)]`

|A| = 6 – 4

= 2 ≠ 0

∴ A-1 exists. A is non singular.

adj A = `[(-3, -4),(1, -2)]`

A-1 = `1/|"A"|`

adj A = `1/2[(-3, -4),(1, -2)]`

Concept: Inverse of a Non-singular Square Matrix
  Is there an error in this question or solution?
Chapter 1: Applications of Matrices and Determinants - Exercise 1.1 [Page 15]

APPEARS IN

Tamil Nadu Board Samacheer Kalvi Class 12th Mathematics Volume 1 and 2 Answers Guide
Chapter 1 Applications of Matrices and Determinants
Exercise 1.1 | Q 2. (i) | Page 15

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