Assume that R2>R2 is a linear transformation such that
Find the standard matrix of T.
Ok, so I get that |1,2|=e1+2e2 and that |3,-1|=3e1-e2, but what do I do from there on? It shows in the solutions that
e1=1/7|1,2| + 2/7|3, -1|
I understand that the are using the same thing from e1+2e2 and 3e1-e2, but where is the divisor of 7 coming from?
Sorry if it's formatted badly, I can scan the original page? Thanks