Activity1a:Angle at centre of circle.
Use this applet to investigate the relationship between the angle subtended at the centre of the circle and the angle subtended at the circumference.
Move point B around the circle to change the sizes of the angles.
Try to answer the questions given below
1. Move point B around the circle, first towards point A and then towards point C. Observe the relationship between the two angles marked. Copy and Complete the sentence below:
" The angle subtended at the centre is __________ the angle subtended at the circumference."
2. What happens when point B is between points A and C? (Hint: You may want to switch off angles p and q and switch on angles r and s)
3. The "picture" for this theorem looks quite different for some different positions of B (e.g. an arrow head, a quadrilateral.....etc). Draw some pictures for your notes to illustrate how this theorem looks for different positions of B.