More Lessons: http://www.MathAndScience.com Twitter: https://twitter.com/JasonGibsonMath In this lesson, you will learn what an imaginary number is and how they compare to a complex number. We will also learn how to use these numbers in math to perform calculations. In order to do this, we first learn that a complex number is the sum of a real number and an imaginary number. The complex numbers thus are represented on a xy plane. One axis is the real axis and the other is the imaginary axis. We can represent imaginary numbers and complex numbers either in rectangular form or in polar form. In polar form, we represent the complex number as a magnitude from the origin and a phase angle measured from the positive x-axis.