Coversine
From specialfunctionswiki
The coversine function $\mathrm{coversin} \colon \mathbb{C} \rightarrow \mathbb{C}$ is defined by the formula $$\mathrm{coversin}(z)=1-\sin(z),$$ where $\sin$ denotes the sine function.
References
- 1964: Milton Abramowitz and Irene A. Stegun: Handbook of mathematical functions ... (previous) ... (next): 4.3.147