Area of Triangle in Terms of Two Sides and Angle/Proof 1

Theorem
The area of a triangle $ABC$ is given by:
 * $\dfrac 1 2 a b \sin C$

where:
 * $a, b$ are two of the sides
 * $C$ is the angle of the vertex opposite its other side $c$.

Proof

 * TriangleAreaTwoSidesAngle.png