(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find the inverse of matrix A

02

30

3. The attempt at a solution

I was thinking of doing a row swap to get a diagonal matrix with nonzero diagonal entries, PA (a.k.a. B). I want this matrix's inverse, B-inverse (easily found by dividing the ones of the identity matrix by the diagonal entries) to serve as a means to get to A-inverse

I want to use this relationship specifically: (B-inverse)(PA)=(A-inverse)(A)=I. I want to multiply all sides by A-inverse to show that (B-inverse)(P)=(A-inverse), but I am really shaky as to how I properly utilize the multiplication rules for matrices in this case.

For example: Would multiplying both sides by A-inverse cancel out A? Wouldn't I be applying A-inverse to the outermost matrix and not even hit A?

To sum: Where I really get lost is how to properly manipulate matrix equations in order to cancel.

Let me know if you have any questions. Sorry I couldn't make the post more visual. Don't know how to draw out matrices.

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# Homework Help: Inverse of a 2X2 matrix

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