1. EXAMPLE 3 Find the inverse of a 3 × 3 matrix Use a graphing calculator to find the inverse of A. Then use the calculator to verify your result. 2 1 – 2 5 3 0 4 3 8 A = SOLUTION Enter matrix A into a graphing calculator and calculate A –1. Then compute AA –1 and A –1 A to verify that you obtain the 3 × 3 identity matrix.

2. EXAMPLE 3 Find the inverse of a 3 × 3 matrix

3. GUIDED PRACTICE for Example 3 5.5. 2 –2 0 2 0 –2 12 –4 –6 A = Use a graphing calculator to find the inverse of the matrix A. Check the result by showing that AA -1 = I and A -1 A = I.

4. GUIDED PRACTICE for Example 3 6.6. – 3 4 5 1 5 0 5 2 2 A = 7.7. 2 1 – 2 5 3 0 4 3 8 A =