Trigonometry –
Circular Functions and The Unit Circle

Oh. Ba. MATH. I mean, ObaMATH is back with an awesome lesson on Circular/Periodic Functions and an introduction to The Unit Circle! Starting in degrees (although it can be done in radians too), the Commander-in-TEACH walks us through the sin and cos of every major angle on The Unit Circle. Specifically, they're the angles from the 30-60-90 and 45-45-90 triangles. YAY MATH!