Inscribed Angle & Centeral Angle

Introduction

Find the relation between angle AOB and angle APB.

Applet

  • Drag the point P to move the point. Are the angles(APB and AOP) changing?
    Drag the point A to change the length of arc AB, and move the point A to observe the value of angle APB and AOB.
    Find the relation between angle AOB and angle APB.

  • Check "Hint" to draw the parallel segments to AP and BP.
    Prove angle AOB = 2 angle APB.