SymPy Gamma

SymPy:

log (-25)

$\log{\left(25 \right)} + i \pi$

Abs(log(25) + I*pi)

$\left|{\log{\left(25 \right)} + i \pi}\right| =$

atan2(*(log(25) + I*pi).as_real_imag()).evalf()

$\operatorname{atan}{\left(\frac{\log{\left(25 \right)}}{\pi} \right)} =$

conjugate(log(25) + I*pi)

$\log{\left(25 \right)} - i \pi =$

See what Wolfram|Alpha has to say.

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