9.5 Inverses of Matrices

Find the inverse of a square matrix, if it exists.

Use inverses of matrices to solve systems of equations.
In this section, we continue our study of matrix algebra, finding the multiplicative inverse, or simply inverse, of a square matrix, if it exists. Then we use such inverses to solve systems of equations.
The Identity Matrix
Recall that, for real numbers, $a\xb71=1\xb7a=a$; 1 is the multiplicative identity. A multiplicative identity matrix is very similar to the number 1.
Example
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