Computing sine and cosine of complex arguments with only real functions

Suppose you have a calculator or math library that only handles real arguments but you need to evaluate sin(3 + 4i). What do you do? If you’re using Python, for example, and you don’t have NumPy installed, you can use the built-in math library, but it will not accept complex inputs. >>> import math >>> […] The post Computing sine and cosine of complex arguments with only real functions first appeared on John D. Cook.