Uniqueness of Linear Transformation from Basis Vectors

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Homework Statement


Suppose A is an m x n matrix.

(a) Let v1 ,...,vn be a basis of ℝn, and Avi = wi ε ℝm, for i = 1,...,n. Prove that the vectors v1,...,vn, w1,...,wn, serve to uniquely specify A.

(b) Write down a formula for A.

Homework Equations


Maybe B = T-1 A S

The Attempt at a Solution



I said S = { v1,...,vn} and T = {w1,...,wn}, then AS=T... I kind of get lost from here.

I think part (b) is suppose to be A = TBS-1... really not too sure though.
 
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So you can write an arbitrary vector as v = a1 v1 + a2 v2 + ... + an vn.
Does the given information unambiguously define Av now?
I.e. can you write down the result without reference to A?
 
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