A3 5.1a & b Starting the Unit Circle! a)HW: p EOO b)HW: p EOE

Definitions Associated with Angles Ray – part of a line that has only one endpoint, and extends forever in the opposite direction Angle – formed by 2 rays Initial side – beginning Terminal side – ending Vertex – endpoints of initial and terminal sides Standard Position – initial side on positive x-axis, vertex at the origin Positive Angle – rotates counterclockwise (across the top) Negative Angle – rotates clockwise (across the bottom)

Definitions Associated with Angles Quadrants and their signs: Acute angle: Right angle: Obtuse angle: Straight angle:

Measuring Angles Central angle – measure of intercepted arc Degrees (angle of rotation) Radians (length of intercepted arc)

Cool Formula Converting between degrees and radians

Examples for angle conversions

Angles in Standard Position -Initial side must be on the positive x-axis -Rotation must be labeled -All complementary angles should be labeled

Draw Angles in Standard Position

Coterminal Angles In simple terms – 2 ways of arriving at the same terminal side. Find an angle that is coterminal and draw the angles in standard position.