Can you prove the formula for projection of a vector using dot products?

Thread starter Bipolarity
Start date Oct 3, 2012
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Projection Vector

Oct 3, 2012

Bipolarity

Is the following statement true? My intuition tells me it is true, but I have been trying to prove it, without much success:

(proj_{v}u ) \cdot (u - proj_{v}u) = 0

It makes complete since if you draw it out in R2, but I am trying to prove it in Rn.

Any ideas?

BiP

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Oct 4, 2012

micromass

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The formula is true. To prove it, can you find another way to write proj_vu?? Try to write it with dot products.

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