Can it be written in the same trig. function?

You may need to use an identity to write an equation in the same trig. function which may then possibly factorise.

In these examples I show you how the following identities :

  • sin(θ) / cos(θ) ≡ tan(θ)
  • sin2(θ) + cos2(θ) ≡ 1

can be used to solve the following trigonometric equations.

Example 1

Trigonometry | Solving Equations using identities (Example 1) | ExamSolutions - youtube Video

Example 2

Trigonometry | Solving Equations using identities (Example 2) | ExamSolutions - youtube Video

Example 3

Trigonometry | Solving Equations using identities (Example 3) | ExamSolutions - youtube Video

Example 4

Trigonometric Equations - Using Pythagorean Identities | ExamSolutions - youtube Video