Difference between revisions of "Q-cos sub q"
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− | * {{BookReference|A Comprehensive Treatment of q-Calculus|2012|Thomas Ernst|prev=q-sin|next=}}: $(6.202)$ | + | * {{BookReference|A Comprehensive Treatment of q-Calculus|2012|Thomas Ernst|prev=q-sin sub q|next=}}: $(6.202)$ |
[[Category:SpecialFunction]] | [[Category:SpecialFunction]] |
Revision as of 15:36, 11 July 2016
The function $\cos_q$ is defined by $$\cos_q(z)=\dfrac{e_q(iz)+e_q(-iz)}{2}=\displaystyle\sum_{k=0}^{\infty} \dfrac{(-1)^kz^{2k}}{(q;q)_{2k}},$$ where $e_q$ denotes the $q$-exponential $e$ and $(q;q)_{2k}$ denotes the $q$-Pochhammer symbol.
Properties
External links
References
- 2012: Thomas Ernst: A Comprehensive Treatment of q-Calculus ... (previous): $(6.202)$