Mathematics for IGCSE & O level - Pythagoras' Theorem And Trigonometry (Section 1 - No. 11)
If two sides of a triangle measure 5 cm and 8 cm, and the included angle is 60 degrees, what is the length of the third side (approximate)?
7 cm
7.02 cm
4.8 cm
8.03 cm
Giải thích
Use Cosine rule