Mathematics for IGCSE & O level - Pythagoras' Theorem And Trigonometry (Section 1 - No. 29)
If the angle between sides a and b of a triangle is known, along with the lengths of sides a and b, which formula can be used to calculate the triangle's area?
Area = 1/2 * a * b
Area = (a + b + c) / 2
Area = 1/2 * a * b * sin(C)
Area = √(s(s-a)(s-b)(s-c))
Explication
The formula involves two sides and the included angle.