Proving Inner Product Space: x not in W, y in W(perp)

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Homework Help Overview

The discussion revolves around proving a property of inner product spaces, specifically regarding the relationship between a vector not in a subspace and a vector in its orthogonal complement.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss using the Gram-Schmidt process to decompose the vector into components from the subspace and its orthogonal complement. Questions arise about the specifics of this decomposition and the implications of the assumptions made about the vector.

Discussion Status

Some guidance has been offered regarding the assumptions necessary for the proof, particularly the non-zero condition of the vector. Participants are exploring the implications of the definitions of subspaces and orthogonal complements, but there is no explicit consensus on the approach yet.

Contextual Notes

There is an assumption that the vector x is non-zero, which is critical to the discussion. The participants are also navigating the definitions and properties of inner product spaces and their subspaces.

jbear12
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Let V be an inner product space, and let W be a finite-dimensional subspace of V. If x[tex]\notin[/tex] W, prove that there exists y[tex]\in[/tex] V such that y [tex]\in[/tex] W(perp), but <x,y>[tex]\neq[/tex] 0.

I don't have a clue...
Thanks
 
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you could start by using something along the lines of gram-schmidt to decompose to x into a sum of vector from W & one from W perp...
 
Umm..I don't really get it. Can you explain more specifically? Thank you.
 
what don't you get?

first you need to assume x is non-zero

x is not contained in W, and as its non-zero, this means it must have a component in W perp , (as V = W + W perp by definition of W perp, sloppy notation here, but hopefully you get the idea)

now consider the dot product of x with the component of x in W perp
 

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