Mathematics for IGCSE & O level - Pythagoras' Theorem And Trigonometry (Section 3 - No. 25)

To find the area of any triangle given two sides and an included angle, which of the following formulas can be used?

Area = 1/2 * base * height

Area = 1/2 * ab * sin C

Area = 1/2 * (a + b) * height

Area = a * b * sin C

Area = 1/2 * a * b * sin C is used in such a case.