1. Measuring Angles – Radian Measure Given circle of radius r, a radian is the measure of a central angle subtended by an arc length s equal to r. The radian measure of an arbitrary angle There are radians in a angle. Why?

2. Using Radian Measure 1.Degree 2 Radian conversions: 2.Measuring angles as fractions of 3.Common angles 4.Finding arc lengths and sector areas using proportions!

3. SOH-CAH-TOA Let be an acute angle in right triangle

4. Two Famous Triangles isosceles 45-45-90 equilateral 30-60-90

5. Know how to do the following 1.Using the famous triangles derive the 6 trig functions for 2.Given any two sides of a right triangle find the values of all six trig. functions 3.Given a side and an angle solve the right triangle (i.e. determine the missing lengths) 4.Given the value of one trig. function, determine the values of the other five

6. Some Miscellaneous Stuff 1.Angular velocity in radians per unit time 2.Alternate area formula for a triangle 3. Complementary angles & co-functions