Triangle inequality in Rubins book

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mynameisfunk
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My problem states:
Given z, w[tex]\in[/tex]C, prove: ||z|-|w||[tex]\leq[/tex]|z-w|[tex]\leq[/tex]|z|+|w|.

Now, I am confused because, isn't it true that ||z|-|w||=|z-w| ? I am using Rudin's book which gives |z|=([z's conjugate]z)1/2
 
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Take z =-2 and w = 2. Does ||z|-|w||=|z-w| still hold?
 
Ah. Thank you. Is it correct from the definition of |z| to think of it as a length? My gf is taking a complex variables class and she had told me that |z|= the length of z, but rudin's book gave the definition above, so i didn't know how to think about it.