9 The Unit Circle – An Introduction Circle with radius of 11 Revolution = 360°2 Revolutions = 720°Positive angles move counterclockwise around the circleNegative angles move clockwise around the circle
19 ExperimentGraph and on the axes below. Whatdo you notice?
20 Coterminal Angles co – terminal Coterminal Angles – angles that end at the same spotwith, joint,or togetherending
21 Coterminal Angles, cont. Each positive angle has a negative coterminal angleEach negative angle has a positive coterminal angle
22 Solving for Coterminal Angles If the angle is greater than 2 pi, subtract 2 pi from the given angle.If the angle is less than 0, add 2 pi to the given angle.You may need to add or subtract 2 pi more than once!!!Trick: Add or subtract the coefficients of pi rather than the entire radian measure
23 Examples: Find a coterminal angle between 0 and 2 pi
24 Your Turn: Find a coterminal angle between 0 and 2 pi
25 Group Exit TicketAre and coterminal? Why or why not?