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

👉 Learn how to find a missing angle of a right triangle. A right triangle is a triangle that has 90 degrees as one of its ...

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.

There are two versions of the cosine rule: Find an unknown side using 𝑎² = 𝑏² + 𝑐² – 2𝑏𝑐 cos𝐴 Find an unknown angle using cos𝐴 = \(\frac{𝑏² + 𝑐² – 𝑎²}{2𝑏𝑐}\) Scientific calculators need to ...