No One-to-One Linear Transformation: V to W

hannahlu92
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Homework Statement



Prove: If V and W are finite-dimensional vector spaces such that dim(W)<dim(V), then there is no one-to-one linear transformation T:V-->W




The Attempt at a Solution


I don't know how to do a well thought out proof.
 
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Hi hannahlu92! :smile:

The first thing you should do with such a statement is trying to find concrete examples. Can you find examples of V and W such that dim(V)<dim(W). Is it true that there doesn't exist such a one-to-one map for these examples? (I.e. is it inuitively true).

Then, to actually start proving it, you'll need to unwind the concept. What does dimension mean? What does one-to-one mean? Can we find some connection between the definition of dimension and the concept of one-to-one maps?
 


thank you for taking the time to try and help me. My final is tomorrow and I still can't understand Linear Algebra
 
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