Saturday 9 May 2009

Trig identities

I always have trouble remembering these, here's a simple derivation using Euler's formula:


Note that the imaginary and real parts are separate so the line , which is real, corresponds to on the top line.

1 comment:

  1. This is also a very good post which I really enjoyed reading. It is not every day that I have the possibility to see something like this..
    half angle identities

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