A complex number is a number of the form a + i*b, where a and b are real numbers, and i is defined to be the square root of negative one. Addition of two complex numbers c1 and c2 is defined to be:
The complex conjugate of a complex number c, denoted c* is defined to be:
Multiplication of two complex numbers c1 and c2 is defined to be:
Euler's Formula for complex numbers states that eix = cos x + i*sin x, this relationship is used in the discrete Fourier transform of Shor's algorithm.