Unknown Transformation Machine

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JoelN
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Homework Statement



You have a unknown Transformation machine T. that transforms from R^4 --> R^3

Vectors U and V are known and the output from T is also known.

Can You calculate the values of T?

Homework Equations


[/B]
What values/information is needed to calcuate T ?

The Attempt at a Solution



I can solve any Vector that is a linear combination of vectors U and/or V but the book doesn't say how to solve what T is and the problem doesn't need it either only to see if you can solve given vectors using linear comb of U and/or V but I am still curious.
Maybe it cannot be solved or if it can its higher mathematics.
 
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The question you posed under "relevant equations" is not a relevant equation. How would you get the transformed vector if you knew the matrix components of the transformation? What are the dimensions of the transformation matrix T?
 
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ehild said:
The question you posed under "relevant equations" is not a relevant equation. How would you get the transformed vector if you knew the matrix components of the transformation? What are the dimensions of the transformation matrix T?

a R^4 --> R^3 Transformer is a 3X4 Matrix, i only know 2 values of 2 linearly independent vectors after going through T. Can i calculate T or do i need more information?
 
How many equations do you have for those 3x4 unknowns?
 
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ehild said:
How many equations do you have for those 3x4 unknowns?

only 2 vectors before and after going through T
 
You know what the transformation does with the subspace spanned by the given U and V vectors, but do not know what happens with the other vectors. Can you fully determine T?
 
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[itex]R^4[/itex] has dimension 4 and u and v, even if they are independent can only span a subspace of dimension 2 (dimension 1 if they are dependent). You need to know what T, applied to two more independent vectors would give in order to completely determine T.
 
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ehild said:
You know what the transformation does with the subspace spanned by the given U and V vectors, but do not know what happens with the other vectors. Can you fully determine T?

HallsofIvy said:
[itex]R^4[/itex] has dimension 4 and u and v, even if they are independent can only span a subspace of dimension 2 (dimension 1 if they are dependent). You need to know what T, applied to two more independent vectors would give in order to completely determine T.

thanks to both.