We use elementary operations to find inverse of a matrix

 

The elementary matrix operations are

  • Interchange two rows, or columns
    Example - R 1 ↔ R 3 , C 2 ↔ C 1

  • Multiply a row or column by a non-zero number
    Example - R 1 →2R 1 , C 3 →(-8)/5 C 3

  • Add a row or column to another, multiplied by a non-zero
    Example - R 1 → R 1 − 2R 2 ,  C 3 → C 3 + 2/3 C 1

Let’s look at each one of them in detail

87.jpg

 

Interchange rows or column

1.jpg

Multiply a row or column by a non-zero number

2.jpg

 

Add a row or column to another, multiplied by a non-zero number

3.jpg

 

 

  1. Chapter 3 Class 12 Matrices
  2. Concept wise

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Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.