Sides and opposite angles

Topic:
Angles

Sides and opposite angles

Using the diagram below you can explore the relationship between the sine of an angle and the length of the opposite side in a triangle.

Question 1

Set the radius at 1. Divide the length of each of the sides, a, b and c by the value of the sine of the opposite angle A, B and C respectively. What do you notice?

Question 2

Set the radius at 2. Again, divide the length of each of the sides a, b and c by the value of the sine of the opposite angles A, B and C respectively. What do you notice this time?

Question 3

  • What conjecture can you make based on what you have seen so far.
  • Test out your conjecture...
  • What generalisation can you come to and how would you express it algebraically?