Is a set of orthogonal basis vectors for a subspace unique?

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Homework Help Overview

The discussion revolves around the uniqueness of orthogonal basis vectors for a subspace, specifically in the context of vector spaces such as R² and R³. Participants are exploring the implications of orthogonality and uniqueness in basis sets.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants are attempting to understand the meaning of uniqueness in the context of orthogonal basis vectors. Some provide examples of orthogonal pairs in R², while others question how these examples relate to the original query about uniqueness.

Discussion Status

The discussion is ongoing, with participants sharing examples of orthogonal basis vectors and questioning the implications of these examples on the uniqueness of such sets. There is recognition of multiple valid orthogonal pairs, but no consensus has been reached regarding the original question.

Contextual Notes

Some participants express confusion about the terminology and the nature of the question, indicating a need for further clarification on the definitions of orthogonality and uniqueness in the context of basis vectors.

DryRun
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Homework Statement
Is a set of orthogonal basis vectors for a subspace unique?

The attempt at a solution
I don't know what this means. Can someone please explain?
I managed to find the orthogonal basis vectors and afterwards determining the orthonormal basis vectors, but I'm not sure what the question is asking for exactly?
 
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Unique means only one. So, for example, in R2, (1,0) and (0,1) are an orthogonal basis. Can you find a different pair giving an orthogonal bases for R2?
 
LCKurtz said:
Unique means only one. So, for example, in R2, (1,0) and (0,1) are an orthogonal basis. Can you find a different pair giving an orthogonal bases for R2?
Thanks for your time, LCKurtz.
To answer your question... Yes, (0,-1) and (-1,0) as well as the following pair (0,0) and (-1,0) and others, like (-1,0) and (0,2), etc.
But what is your point? I don't see how that answers my original question.
 
sharks said:
Thanks for your time, LCKurtz.
To answer your question... Yes, (0,-1) and (-1,0) as well as the following pair (0,0) and (-1,0) and others, like (-1,0) and (0,2), etc.
But what is your point? I don't see how that answers my original question.

You don't?? Your question was whether a subspace had a unique (meaning only one) set of basis vectors. You have just mentioned several. And you could find entirely different ones by rotating them too.
 
OK, i missed that point, as my mind was focused more on the actual orthogonal basis vectors, which is a 3x3 matrix, which i assume would not be unique either. Thanks!
 

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