inverses-of-matrices

Inverse of a matrix

What is an inverse of a matrix?

• The determinant can be used to find out if a matrix is invertible or not:

  • If , then  is invertible

  • If , then  is singular and does not have an inverse

• The inverse of a square matrix is denoted as the matrix  

• The product of these matrices is an identity matrix, 

• You can use your calculator to find the inverse of matrices

  • You need to know how to find the inverse of 2×2 and 3×3 matrices by hand

• Inverses can be used to rearrange equations with matrices:

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