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cepheid
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#4
Nov23-11, 12:09 AM
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Basic Integral without Basic Concept


Quote Quote by dimension10 View Post
I think this is not possible. Maybe your friend considers

[tex]\sin\theta=\frac{{e}^{i\theta}-{e}^{-i\theta}}{2i}[/tex]
[tex]\cos\theta=\frac{{e}^{i\theta}+{e}^{-i\theta}}{2}[/tex]

to be definitions of sine and cosine?
Assuming we're allowed that definition of cosine, then that also works.

Quote Quote by dimension10 View Post
But sine and cosine are defined to y/r and x/r respectively.
I'm not sure I understand your statement here. Can you clarify?