Moton of Fly Applet, Clip 2, Investiagation of Quadrants, 3:16

• Based on a student comment about finding a coordinate in the third quadrant the teacher leads an investigation of quadrants and the outputs of the inverse trig function.
• The teacher uses the applet to put the ray in the third quadrant and asks about what the value for the inverse trig functions will be. Notice that he is still requiring the students to give the units for their answers. Based on the student's answer, he shows that they would not be in the third quadrant.
• This is an opportunity to create a need for reference angles as the students are seeing that they need to take their arclength and add it to Pi. The teacher does a nice job here of showing how both student suggestions are identical. The teacher also takes time to show on the diagram how they both make sense.