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smyroosh
Nov3-09, 04:33 PM
How to prove the following inequality: for complex z such that Re z < 0 :

\left| e^z-1\right| < \left| z\right| ?

elibj123
Nov3-09, 05:58 PM
use the identities

\left|z\right|^{2}=z\bar{z}

and

\bar{e^{z}}=e^{\bar{z}}

since both sides of the inequality are positive
you can square it up

smyroosh
Nov4-09, 03:14 AM
What next?