ฟังก์ชันเลขชี้กำลัง

Also known as exponential, exponential function of base a, exponential map

mathematical function with a constant base and a variable exponent, denoted exp_a(x) or a^x

General definition: exp ⁡ z = e z {\displaystyle \exp z=e^{z}}
Domain: C {\displaystyle \mathbb {C} }
Image: { ( 0 , ∞ ) for z ∈ R C ∖ { 0 } for z ∈ C {\displaystyle {\begin{cases}(0,\infty )&{\text{for }}z\in \mathbb {R} \\\mathbb {C} \setminus \{0\}&{\text{for }}z\in \mathbb {C} \end{cases}}}
Value at 1: e
Fixed point: − W n (−1) for n ∈ Z {\displaystyle n\in \mathbb {Z} }
Reciprocal: exp ⁡ ( − z ) {\displaystyle \exp(-z)}
Inverse: Natural logarithm , Complex logarithm
Derivative: d d z exp ⁡ z = exp ⁡ z {\displaystyle {\frac {\mathrm {d} }{\mathrm {d} \!\,z}}\exp z=\exp z}
Antiderivative: ∫ exp ⁡ z d z = exp ⁡ z + C {\displaystyle \int \exp z\,dz=\exp z+C}
Taylor series: exp ⁡ z = ∑ n = 0 ∞ z n n ! {\displaystyle \exp z=\sum _{n=0}^{\infty }{\frac {z^{n}}{n!}}}