Linear Algebra: Projection onto a subspace

Kisa30
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Homework Statement



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That is the question. The answer on the bottom is incorrect

Homework Equations



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I believe that is the formula that is supposed to be used.

The Attempt at a Solution



All I really did was plug in the equation into the formula but there is something I am missing because the answer is incorrect

Projection = (41/65)v1 + (26/5)v2
This is what I got after inserting the projection formula.
And in the first image, on the bottom it shows the final solutions I got.


Please help me figure out how to do this question and where I went wrong.

Thanks in advanced!
 
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Just a thought, but do you have to provide the solutions in a specific number format (i.e. rounded to a certain number of figures) or maybe as exact fractions?
 
I don't think it's important, no. =)
 
What conditions must v1 and v2 meet so that the formula can be used?

An alternative approach would be to find a vector x that's perpendicular to V, and find the projection of v onto x, and subtract that from v. What's left over will lie in the subspace V.
 
Apparently the problem is that it's not orthogonal.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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