Prove Det B = Det A for Invertible Matrix T

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Homework Statement


if T is an invertible matrix, and A=(T^-1)B*T, prove that det B = det A


Homework Equations



A(BC) = (AB)C


The Attempt at a Solution


im not certain if inverse T and T will cancel to 1
A=B
det A = det B
 
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What do you know of the determinant of the product of matrices and of the determinant of inverses? Use those facts and the proof should be immediate.
 
oh would be it
det(A) = det(T^-1)det(BT)?
 
Yes, but continue further.
 
oh alright, i think i got it.
det(A) = det(B)det(T)^-1det(T)
det(A) = det(B)

thanks for the help!
 
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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