👉 Learn how to write a given sum or difference of two angles formula expression as a single sum/difference of angles trigonometric function. To do this, we first identify the trigonometric function ...

Being able to identify which formula to use, sine or cosine, and when, is necessary to answer questions on this topic successfully. Check you are confident in how to use the sine and cosine rules.

👉 Learn how to evaluate the tangent of a half-angle. When given the value of the tangent of an angle, we can evaluate the tangent of half the angle using the tangent half-angle formula. When the ...