Prove Euler\'s identity

By Euler formula,

e^(i@) = cos@ + isin@

So, e^(i pi) = cospi + isinpi = -1 + i(0) = -1

So, e^(i pi) + 1 = -1 + 1 = 0

@ is theta

2010-03-05 00:36:27 補充：
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