A complex number consists of a real part and an imaginary part . (We choose and to be real numbers.) is the square root of -1.
The complex conjugate of is . (Just change the sign of all the .)
The absolute square of a complex number is calculated by multiplying it by its complex conjugate.
We will use complex exponentials all the time.
We can write and .
As with other exponentials, we can multiply them by adding the exponents.
Jim Branson 2013-04-22