Nullspace of Matrix H: Proving Basis with Independent Rows

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Note: I don't know LaTeX that well, hence I have done my working in the images.

Homework Statement



Show that the rows of G are a basis for the null space of H (part of this question will be to show the independence explicitly).

http://img.skitch.com/20090415-f6gewnam8bq6m971y9s7cam55q.preview.jpg
Click for full size - Uploaded with plasq's Skitch[/color]

Homework Equations



Nullspace of H is the vector space of x, in which Hx=0. Basis is set of independent vectors that define this space.

The Attempt at a Solution



http://img.skitch.com/20090415-reqmbp49jacrhkme1886t1j5sx.jpg


http://img.skitch.com/20090415-gwtu1hpgep9aun89isp16jxhwn.jpg

Any help you can provide would be greatly appreciated.
 
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The rows of the vector G given in the problem statement are not in the nullspace of H. Your first attempt correctly identified a basis for the nullspace. The original problem is wrong.
 
The question was right, elsewhere it mentioned that the work was in mod2.
 
You REALLY should have said it was mod 2. Omitting that is actually criminal. There is no difference between -1 and +1 mod 2. Hence why are you complaining about sign changes?
 
I was complaining when I did not realize I was working in mod 2. I only saw it was mod 2 after re-reading the question again and again.
 
Ok, your complaint is shared. The question should have been more clearly stated.
 
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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