Finding a Basis for Subspace in R^4: Linear Algebra Tips

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Help! Find a basis.
Find a basis for the subspace of R^4 spanned by, S={(6,-3,6,340, (3,-2,3,19), (8,3,-9,6), (-2,0,6,-5)

Figured I would set up the linear combination to test for independence.
 
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Do you know how to set up these four vectors as columns to make a 4x4 matrix?

Have you done row reducing?

Because that would also be an approach to determining if they are linearly independent.
 
I made up the columns, solved for rref, and came up with the trivial solution
 
As long as you got it to RREF, then you can see if there is a pivot in each column, if there is, then these vectors span R4. If there is not a pivot in each, then they do not span R4.

Good luck!
 
If the determinant of the matrix these vectors make is 0 then some of them are linearly dependent.
 
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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