Complex numbers, complex functions and complex analysis in general are part of an important branch
of mathematics. They find wide application in solving real scientific and engineering problems.
In mathematics, a complex number is a number of the form z = x + iy, where:
 is the complex variable
 x and y are real numbers
 is the imaginary unit, with the propertyi^{2} = 1.
The real number x is called the real part of the complex number, and the real number y is the imaginary
part. Real numbers may be considered to be complex numbers with imaginary part set to zero. That is,
the real number x is equivalent to the complex number x + 0i.
At Keystone Mining Post we show how complex numbers can be added, subtracted, multiplied and divided just like real numbers. The next pages
show the implementation of trigonometric functions.
