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Inverse Matrices

Well, guess what?

It works the same way with matrices!

A^( -1 ) times A = I

* Remember that inverses undo each other!

So, if our A^( -1 ) guy is correct, if we multiply him by A, we should get the identity guy.

By the way, the order won't matter:

A times A^( -1 ) = I

* This is the one time that multiplication of matrices is commutative!

OK, so let's check our A^( -1 ) :

A^( -1 ) times A

[ row 1: 2 , 3 row 2: -4 , -5 ] times [ row 1: -( 5 / 2 ) , -( 3 / 2 ) row 2: 2 , 1 ] = [ row 1: 1 , 0 row 2: 0 , 1 ] ... the answer is I

Woo hoo!  It worked!  Cool!

Believe me, you're going to be stinkin' excited
when you get these right, too!