Difference between revisions of "Weierstrass factorization theorem"

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=Examples of Weierstrass factorizations=
 
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{{:Weierstrass factorization of cosine}}

Revision as of 06:17, 20 March 2015

Examples of Weierstrass factorizations

Theorem

The following formula holds: $$\sin(z) = z \displaystyle\prod_{k=1}^{\infty} \left( 1 - \dfrac{z^2}{k^2\pi^2} \right),$$ where $\sin$ denotes the sine function and $\pi$ denotes pi.

Proof

References

Theorem

The Weierstrass factorization of $\cos(x)$ is $$\cos(x) = \displaystyle\prod_{k=1}^{\infty} \left( 1 - \dfrac{4x^2}{\pi^2 (2k-1)^2} \right).$$

Proof

References