Complex numbers - polar form, calculations and geometrical applications

The first resource introduces the technique for writing a complex number z=a+bi in (trigonometric) polar form, r(cos (theta)+ i sin(theta)), there are few examples of converting from one form into the other (to do as a class), and then an exercise of 30 questions for students to do. The next section introduces the exponential polar form re^(i theta), a few examples of converting from one form into the other (to do as a class), and then an exercise of questions for students to do. The exercise includes questions that get students to consider what z* and -z look like in both polar forms, as well as investigating multiplying and dividing complex numbers in polar form. Answers to the exercises are included.

The second resource begins with a reminder of how to multiply/divide complex numbers in polar form, followed by an exercise of questions to practise. The remaining 3 pages cover the geometrical effect of multiplying, with several examples for students to learn from. Fully worked solutions are included.

The final resource focuses on examination-style questions that consider the geometric effect of multiplying by a complex number in polar form. Fully worked solutions are included.