The Sine Law (animated)

Sine Law Let’s begin with the triangle  ABC:

A CB Sine Law Let’s begin with the triangle  ABC:

A CB c a b Sine Law Let’s begin with the triangle  ABC:

A CB c a b Sine Law Let’s begin with the triangle  ABC: h D altitude, h

A CB c a b Sine Law Let’s begin with the triangle  ABC: h D Note this ratio in triangle  ABD:

A CB c a b Sine Law h D Note this ratio in triangle  ABD: Note this ratio in triangle  ABC:

A CB c a b Sine Law h D Note this ratio in triangle  ABD:

A CB c a b Sine Law h D

A CB c a b h D Therefore, we get:

A CB c a b Sine Law Therefore, we get: and, if we follow the same method for sides A and C: In conclusion: The Sine Law: