Determinants as Area or Volume

Lonely Lemon
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Homework Statement



If S is a parallelepiped determined by v1=(1, 1, 0) and v2= (3, 2, 1) and v3=(6, 1, 2) and T: R3--> R3 by T(x)=Ax, find the volume of T(S)

Homework Equations



{volume of T(S)}=|det A|.{volume of S}

The Attempt at a Solution



A is [v1 v2 v3] and the |A| = 9 by my calculations. I thought this was the volume, but the answer to the questions is given as 24. Please help!
 
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So the vectors define both the solid S and the mapping A? Just want to make sure you've described the problem as assigned.
 
I assume so, that's the problem posed word for word. T: R3-->R3 is the linear transformation determined by a 3x3 matrix A, and S is the a parallelepiped in R3, so the vectors define both?
 
If that's true, then shouldn't the volume of T(S) be a perfect square? By the way, I get det A=3, so you might want to recheck your calculations.
 
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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