# Complex numbers and complex planes

### Complex numbers and complex planes

Now that we know the basics of imaginary numbers, let's expand our knowledge and learn about another concept that is closely tied to imaginary numbers – complex numbers, a number that is consisted of a real part, and an imaginary part. In this section, we will learn what makes up a complex number, as well as how to plot on a complex plane.

#### Lessons

• Introduction

• 1.
For the following quadratic equations,
i) find and classify the roots
ii) plot the roots on the complex plane
a)
$y=x^2-1$

b)
$y=x^2+1$

c)
$y=-x^2+2x-5$

• 2.
Given that function $f(x)=2x^2-2x+3$, find the roots of the function