S. D. V. Stephens

notes / Integrated Mathematics / chapter 16: Parametric Equations, Polar Coordinates and Complex Numbers

16.3 Basics of Complex Numbers

In progress: these notes stop partway.

This page plots complex numbers as points in the plane and starts on the modulus.

The complex plane

Problem 16.3.1. (a) Let ; plot , , and .

(b) For all , how are and related? What about and ?

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(a) , , :

In the complex plane, the points w = 2 + 3i, its conjugate 2 - 3i, and -w = -2 - 3i.

Real and imaginary parts

Problem 16.3.2. (a) Let . Express in terms of .

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Write , so and Also , so but that still has in it (as ).

Two further exercises are only started in the notes: one plots and four unlabelled points, and the other is blank.