Find basis B given the transition matrix and B'

fattycakez
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Homework Statement


The Matrix P =
1 0 3
1 1 0
0 3 1
is the transition matrix from what basis B to the basis B' = {(1,0,0),(1,1,0),(1,1,1) for R3?

Homework Equations


[v]B=P[v]B'

The Attempt at a Solution


I'm looking at a theorem in my book that says

" if P is the transition matrix from a basis B' to a basis B for a finite-dimensional vector space V, then P is invertible and P-1 is the transition matrix from B to B'. "

So does the inverse of P give the basis B? Please tell me how wrong I am :)
 
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I will gladly tell you how wrong you are. Not at all (if I understand you correctly)
You have ## \bf{P} \cdot \bf{B} = \bf{B'} ## Multiply both sides by ## \bf{P}^{-1} ## and you have solved your equation for B.
 
BiGyElLoWhAt said:
I will gladly tell you how wrong you are. Not at all (if I understand you correctly)
You have ## \bf{P} \cdot \bf{B} = \bf{B'} ## Multiply both sides by ## \bf{P}^{-1} ## and you have solved your equation for B.
Awesome, thank you! \m/
 
No problemo
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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