Mathematics for IGCSE & O level - Pythagoras' Theorem And Trigonometry (Section 3 - No. 8)
Which rule is typically used when you need to find missing sides and angles in a non-right-angled triangle given two sides and an included angle?
Pythagorean Theorem
Sine Rule
Cosine Rule
Tangent Rule
Explication
The Cosine Rule helps in solving for missing sides and angles if we are given two sides and an included angle.