Proving Nonzero Vector Intersection in 3D Subspaces of R5

RyanV
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Homework Statement


Prove that if V and W are three dimensional subspaces of R5, then V and W must have a nonzero vector in common.


Homework Equations


NA


The Attempt at a Solution


I've attempted to set up the problem by writing out,

V = { (1, 0, 0, 0, 0), (0, 1, 0, 0, 0), (0, 0, 1, 0, 0) }
W = { (0, 0, 0, 1, 0), (0, 0, 0, 0, 1), (1, 1, 0, 0, 0) }

After that, I'm lost.

I don't really like vector spaces because I don't understand it very well. So could whoever explain please explain thoroughly? =P I would help a lot because I want to know what's going on! hehe, thanks in advance =)
 
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rather than narrowing in on a single case, think aobut linear independence... what is the maximal number of linearly independent vectors, in any subspace of R^3?

similarly, how many vectors are in a the basis for R^5?
 
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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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