Linear Functionals Inner Product

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wurth_skidder_23
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Assume that [tex]m<n[/tex] and [tex]l_1,l_2,...,l_m[/tex] are linear functionals on an n-dimensional vector space
[tex]X[/tex].

Prove there exists a nonzero vector [tex]x[/tex] [tex]\epsilon[/tex] [tex]X[/tex] such that [tex]< x,l_j >=0[/tex] for [tex]1 \leq j \leq m[/tex]. What does this say about the solution of systems of linear equations?This implies
[tex]l_j(x)[/tex] [tex]\epsilon[/tex] [tex]X^\bot[/tex] for [tex]1 \leq j \leq m[/tex] or [tex]l_j(x)=0[/tex] for [tex]1 \leq j \leq m[/tex]. Since it is stated in the problem that [tex]l_1,l_2,...,l_m[/tex] are linear functionals on the vector space X, [tex]l_j(x)=0[/tex]. Does this reasoning even help me find the proof? I am stuck.

If you have trouble reading this, it is also at http://nirvana.informatik.uni-halle.de/~thuering/php/latex-online/olatex_33882.pdf
 
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I don't know what [itex]X^\perp[/itex] means, nor why you are taking the inner product rather than just applying the functional to the vector. You'll obviously need to involve n and use n>m, and the easiest way to use this is appeal to the existence of a basis with n elements.
 
so basically I'm trying to prove that for some nonzero [tex]x[/tex], [tex]l_j(x)=0[/tex]?