Mathematics for IGCSE & O level - Pythagoras' Theorem And Trigonometry (Section 1 - No. 8)
What information do you need to use the cosine rule to find the length of a side?
Two sides and one non-included angle.
All three sides.
Two sides and the included angle.
Two angles and one side.
解释
The Cosine Rule requires two sides and the included angle to solve for a side.