Mathematics for IGCSE & O level - Pythagoras' Theorem And Trigonometry (Section 6 - No. 12)
Which of the following accurately describes the cosine rule?
A method to find side lengths in non-right angled triangles.
A method to find angles in non-right angled triangles.
A method to find area of a triangle.
A method to be used in right triangles only
Explication
Cosine rule is used to find sides and angles of non-right angled triangles