From 45a4bb100ca5aea14554f265ffc09e981d79a36c Mon Sep 17 00:00:00 2001 From: joshuab <> Date: Tue, 29 Jun 2010 15:24:17 +0000 Subject: tex --- ClassJune26.page | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'ClassJune26.page') diff --git a/ClassJune26.page b/ClassJune26.page index faa516c..15c603a 100644 --- a/ClassJune26.page +++ b/ClassJune26.page @@ -153,7 +153,7 @@ and add them up just fine, so we can exponentiate complex values of $z$. We know what happens to real values, what happens to pure imaginary ones? Let $y\in\mathbb{R}$. Then $\begin{array} -e^{iy} & = & 1+iy+\frac{(iy)^{2}}{2!}+\frac{(iy)^{3}}{3!}+\frac{(iy)^{4}}{4!}+\frac{(iy)^{5}}{5!}+\cdots\\ + e^{iy} & = & 1+iy+\frac{(iy)^{2}}{2!}+\frac{(iy)^{3}}{3!}+\frac{(iy)^{4}}{4!}+\frac{(iy)^{5}}{5!}+\cdots\\ & = & 1+iy-\frac{y^{2}}{2!}-i\frac{y^{3}}{3!}+\frac{y^{4}}{4!}+i\frac{y^{5}}{5!}+\cdots\\ & = & (1-\frac{y^{2}}{2!}+\frac{y^{4}}{4!}+\cdots)+i(y-\frac{y^{3}}{3!}+\frac{y^{5}}{5!}-\cdots)\\ & = & \cos y+i\sin y\end{array}$ -- cgit v1.2.3