👉 Learn how to solve equations using half-angle identities. To do this we will replace every trig function with half angles ...

👉 Learn how to evaluate inverse trigonometric functions. When an angle is unknown but the value of one of the trigonometric ...

a missing side in a right-angled triangle when another side and an angle are known. a missing angle in a right-angled triangle when two sides are known. In these formulae, the Greek letter θ (theta) ...

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.