A fun aspect of trig is all the relations and expression that come from adding and subtracting angles inside the unique trig functions! These relations can be super helpful when solving complex trigonometric problems. This topic’s content is just special cases of adding and subtracting trigonometric angles. This is part of the Prelim Maths Extension 1 Syllabus from the topic Trigonometric Functions: Further Trigonometric Identities. In this post, we will explore double angles.
Some equations for this topic are:
- sin(2A) = 2 sin(A) cos(A)
- cos(2A) = cos^2(A)- sin^2(A)
- tan(2A) = 2tan(a)/(1-tan^2(A))
Let’s explore this through the following video!
https://www.youtube.com/watch?v=-Wu6ekO2Sdw
