Contour
Proof of Sine Rule, Cosine Rule, Area of a Triangle
Work your way through the 3 proofs.
Click on the 'hint' button and use this to help you write down what the correct next step is.
Then click on the 'step' button and check if you got the same working out.
Once you are done with a page, click on the button 'next' on the bottom right to get to the next page.
