Double Angle Formulae is a part of the VCE Specialist Maths topic Functions and Graphs.
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.
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))
How to Use the Formulae
Watch this video to learn now to use the double angle formulas for sine, cosine and tangent.
Want to learn more? Check out more of our VCE Mathematics resources here!