Lesson: De Moivre’s Theorem for Trigonometric Identities Mathematics

In this lesson, we will learn how to use de Moivre’s theorem to obtain trigonometric identities.

Lesson Plan

Students will be able to

use de Moivre’s theorem to find multiple-angle formulae,
use de Moivre’s theorem to find expressions for the powers of trigonometric identities,
use de Moivre’s theorem to find trigonometric identities that are used to evaluate trigonometric integrals and solve trigonometric equations.

Q1:

Express in terms of the sines of multiples of .

Q2:

Which of the following is equivalent to ?

Q3:

Using de Moivre’s theorem, find the exact value of .