Question

I need to compute imaginary exponential in C.

As far as I know, there is no complex number library in C. It is possible to get e^x with exp(x) of math.h, but how can I compute the value of e^(-i), where i = sqrt(-1)?

Answer 1

Note that exponent of complex number equals:

e^(ix) = cos(x)+i*sin(x)

Then:

e^(-i) = cos(-1)+i*sin(-1)