(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I don't know if I'm posting in the right area, but here is the question:

From the inequality: la dot bl= lal lbl lcos(theta)l is less than or equal to lal lbl

Deduce the triangle inequality:

la+bl is less than or equal to lal +lbl

2. Relevant equations

3. The attempt at a solution

I am not even sure where to begin :(

I'm wondering if I could use numbers to prove it, but that doesn't seem right.

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# Homework Help: Vector Proofs

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