Difference between revisions of "Sinc"

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File:Sinc.png|Plot of $\mathrm{sinc}$ on $[-15,15]$.
 
File:Sinc.png|Plot of $\mathrm{sinc}$ on $[-15,15]$.
 
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=Properties=
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<strong>Theorem:</strong> The following formula holds:
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$$\mathrm{sin}(x)=\displaystyle\prod_{k=1}^{\infty} \cos \left( \dfrac{x}{2^k} \right).$$
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<strong>Proof:</strong> █
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=Videos=
 
=Videos=
 
[https://www.youtube.com/watch?v=xEFi0xQRCKI Infinite Product Evaluation with the Sinc Function]
 
[https://www.youtube.com/watch?v=xEFi0xQRCKI Infinite Product Evaluation with the Sinc Function]

Revision as of 02:09, 30 April 2015

The $\mathrm{sinc}$ function is defined by $$\mathrm{sinc}(x) = \left\{ \begin{array}{ll} \dfrac{\sin x}{x} &; x \neq 0 \\ 1 &; x=0. \end{array} \right.$$

Properties

Theorem: The following formula holds: $$\mathrm{sin}(x)=\displaystyle\prod_{k=1}^{\infty} \cos \left( \dfrac{x}{2^k} \right).$$

Proof:

Videos

Infinite Product Evaluation with the Sinc Function