## A Conversation for The Euler Equation

### Other Deriviation

e to the x Started conversation May 7, 2001

Weird.

I learned a different way to derive this formula. How I learned it was by taking the series expansion of e^x and replacing all x's with ix's. Each even term has i to an even power, so it becomes a real number, and all odd terms become imaginary. You can then seperate this series into real and imaginary parts, and it turns out that the real part is the series expansion of cos(x) and the imaginary part is the series expansion of sin(x).

### Other Deriviation

Joe aka Arnia, Muse, Keeper, MathEd, Guru and Zen Cook (business is booming) Posted Jul 15, 2001

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### Other Deriviation

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