document.write( "Question 436449: Consider only vectors in R^3
\n" ); document.write( "Proof: if v dot w = 0 for all v, then w = 0
\n" ); document.write( "Please help, i tried through a counterexample and my professor didn't like it.
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Algebra.Com's Answer #301971 by robertb(5830)\"\" \"About 
You can put this solution on YOUR website!
It follows from the hypothesis that \"w%2Aw+=+abs%28w%29%5E2+=+0\" ==> \"abs%28w%29+=+0\". Only one vector has 0 magnitude, and that is the zero vector. Hence w is the zero vector. \n" ); document.write( "
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