Difference between revisions of "Taylor series of cosine"

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<strong>[[Taylor series of cosine|Proposition]]:</strong> [[Cosine|$\cos$]]$(x) = \displaystyle\sum_{k=0}^{\infty} \dfrac{(-1)^k x^{2k}}{(2k)!}$
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<strong>[[Taylor series of cosine|Proposition]]:</strong> The following formula holds:
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$$\cos(z)= \displaystyle\sum_{k=0}^{\infty} \dfrac{(-1)^k z^{2k}}{(2k)!},$$
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where $\cos$ denotes the [[cosine]] function.
 
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<strong>Proof:</strong> █  
 
<strong>Proof:</strong> █  
 
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Revision as of 05:43, 8 February 2016

Proposition: The following formula holds: $$\cos(z)= \displaystyle\sum_{k=0}^{\infty} \dfrac{(-1)^k z^{2k}}{(2k)!},$$ where $\cos$ denotes the cosine function.

Proof: