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cwaller
Dec 17, 2010, 07:12 PM
A=[2-5]
[2 6] I inverted to [6 5]
[-2 2] Don't know what to do next to solve.

jcaron2
Dec 17, 2010, 08:22 PM
The inverse of a square matrix is the adjoint divided by the determinant. So far you've successfully found the adjoint matrix. Now, to finish doing the inverse, you just need to divide everything by the determinant of A, and you're done. Your 6 should be 6/22, your 5 should be 5/22, etc.

When you're all done, you can check your work by doing the matrix multiplication A * inv(A) and the result should be the identity matrix [1 0][0 1].

Good job so far.