Task 1: Recap on acute angles
Watch the following youtube video.
Task 2: Obtuse Angles
Step 1: Extend the definition of trigonometric ratios.
What will cosine theta and sine theta be if the circle is of radius r instead?
Do the Investigation on page 175 in your textbook.
What can you conclude from the Investigation?
Look at the Conclusion tab for the answers of Question 1 and 2. Do Practise Now 1 and 2 in your notebook.
Give yourself a pat on the back. You have completed your elearning! :D
Answer: cosine theta = x/r and sine theta = y/r
Answer: sin A = sin (180-A) and cos A = -cos (180-A)