Assumptions:
TeX:
\operatorname{atan}\!\left(z\right) = \sum_{k=0}^{\infty} \frac{{\left(-1\right)}^{k} {z}^{2 k + 1}}{2 k + 1}
z \in \mathbb{C} \,\mathbin{\operatorname{and}}\, \left|z\right| \lt 1Definitions:
| Fungrim symbol | Notation | Short description |
|---|---|---|
| Atan | Inverse tangent | |
| Pow | Power | |
| Infinity | Positive infinity | |
| CC | Complex numbers | |
| Abs | Absolute value |
Source code for this entry:
Entry(ID("4e5947"),
Formula(Equal(Atan(z), Sum(Div(Mul(Pow(-1, k), Pow(z, Add(Mul(2, k), 1))), Add(Mul(2, k), 1)), Tuple(k, 0, Infinity)))),
Variables(z),
Assumptions(And(Element(z, CC), Less(Abs(z), 1))))