Quick Matrix Question

GuitaristOfRa

Looking over a proof of something, I was confused at this step:

We end up with: R[tex]^{T}[/tex] R = I (the identity matrix)
This must mean that R[tex]^{-1}[/tex] = R[tex]^{T}[/tex]

This is confusing me because I know that A A[tex]^{-1}[/tex] = I , but in the R case the transpose is on the left side instead of the right, and it seems to me that it matters what order the matrices are multiplied.

homology

Okay, start with [tex]AA^{-1}=I[/tex]. Can you turn this into [tex]A^{-1}A=I[/tex]?