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**Shelled****Member**- Registered: 2014-04-15
- Posts: 44

Prove that given any two vectors the following holds:

||u| - |v|| <= |u-v|

Hint start with u = u - v + v

I know that I'll need to use the triangular inequality at some point, however, not sure how to start it off.

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**Olinguito****Member**- Registered: 2014-08-12
- Posts: 649

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[*]

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Now interchange **u** and **v** and get

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[*]

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Result follows.

*Bassaricyon neblina*

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**Shelled****Member**- Registered: 2014-04-15
- Posts: 44

Why is it that u = u - v + v can be written as the length and absolute value?

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