I really like Euler's Formula, which states e^(ix) = cos(x) + isin(x). I especially like it for x=pi because it becomes e^(i*pi) = -1 + 0, which has all kinds of cool elements including, 1, 0, pi, e, i, and both positive and negative numbers.
back to favorite theorems page: MA_453_Spring_2009_Walther_Week_1
