Span of an infinite set. Exam Question.

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SUMMARY

The discussion centers on the linear independence of an infinite set Z and its implications for the dimensionality of the vector space V=. It is established that if every pair of distinct elements in Z is linearly independent, then Z cannot form a finite-dimensional space. The reasoning provided indicates that a basis for a finite-dimensional space requires a finite number of linearly independent vectors, contradicting the infinite nature of Z. An example using unit vectors in the first quadrant illustrates that while pairs can be independent, the entire set cannot be finite-dimensional.

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  • Understanding of linear independence and vector spaces
  • Familiarity with the concept of basis in linear algebra
  • Knowledge of infinite sets and their properties
  • Basic comprehension of dimensionality in vector spaces
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Homework Statement



Suppose V=<Z> where Z is an infinite set, So Z spans V.
Suppose that every pair of distinct elements of Z is linearly independent.
Is it possible that V is finite dimensional? Justify your answer.

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The Attempt at a Solution


All the vectors must be linearly independent if any two are so...
I don't think you can as a basis for the space would have infinite linaerly independent vectors.
 
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All of the vectors don't have to be linearly independent just because every pair is. Let Z be the set of all unit vectors in the first quadrant in the two dimensional plane. Since they all point in different directions, any pair is linearly independent.
 

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