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author | siveshs <siveshs@gmail.com> | 2010-07-02 03:24:56 +0000 |
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committer | bnewbold <bnewbold@adelie.robocracy.org> | 2010-07-02 03:24:56 +0000 |
commit | 99524349daae12733b5d48fb220c1d5b551219c6 (patch) | |
tree | 77740b933fe821963aeed35ef7fd0f30150317b0 | |
parent | bd74caeb943c803ea175aed89e059e2fd6743781 (diff) | |
download | afterklein-wiki-99524349daae12733b5d48fb220c1d5b551219c6.tar.gz afterklein-wiki-99524349daae12733b5d48fb220c1d5b551219c6.zip |
still testing
-rw-r--r-- | Fourier Series.page | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/Fourier Series.page b/Fourier Series.page index c90f37e..ad3c6d8 100644 --- a/Fourier Series.page +++ b/Fourier Series.page @@ -7,10 +7,10 @@ To show that Fourier series is plausible, let us consider some arbitrary trignom $1. \cos(2x) = 1 - 2 \sin^2(x)$ $$\begin{array}{ccl} -e^{iy} = 1+iy+\frac{(iy)^{2}}{2!}+\frac{(iy)^{3}}{3!}+\frac{(iy)^{4}}{4!}+\frac{(iy)^{5}}{5!}+\cdots\\ - = 1+iy-\frac{y^{2}}{2!}-i\frac{y^{3}}{3!}+\frac{y^{4}}{4!}+i\frac{y^{5}}{5!}+\cdots\\ - = (1-\frac{y^{2}}{2!}+\frac{y^{4}}{4!}+\cdots)+i(y-\frac{y^{3}}{3!}+\frac{y^{5}}{5!}-\cdots)\\ - = \cos y+i\sin y\end{array}$$ +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}$$ ##What is the Fourier series actually?</b> |