Arcus Tangens
Function
definiendum | $\arctan: \{z\in\mathbb C\mid |z|\le 1, z\neq \pm i\}\to\mathbb C$ |
definiendum | $\arctan(z):=\sum_{n=0}^\infty (-1)^n\frac{1}{2n+1} z^{2n+1} $ |
Theorems
$\frac{{\mathrm d}}{{\mathrm d}z}\arctan(z)=\frac{1}{1+z^2}$ |
---|
References
Wikipedia: Inverse trigonometric functions