1. I would like to give credit to the following people below for the wonderful PowerPoint presentation. Thank you very much, Ms. Garcia Moy Yee Ping 3 Szeto Kwok Fai 2 Chau Ping 1

2. Trigonometry ( 三角幾何 ) means “ Triangle” and “Measurement” Introduction Trigonometric Ratios

3. Adjacent , Opposite Side and Hypotenuse of a Right Angle Triangle .

4. Adjacent side Opposite side hypotenuse 

5. hypotenuse Adjacent side Opposite side 

10. Exercise 1 In the figure, find sin  Sin  = Opposite Side hypotenuses = 4 7  = 34.85  (corr to 2 d.p.)  4 7

11. Exercise 2 11 In the figure, find y Sin35  = Opposite Side hypotenuses y 11 y = 6.31 (corr to 2.d.p.) 35 ° y Sin35  = y = 11 sin35 

15. Exercise 3  3 8 In the figure, find cos  cos  = adjacent Side hypotenuses = 3 8  = 67.98  (corr to 2 d.p.)

16. Exercise 4 6 In the figure, find x Cos 42  = Adjacent Side hypotenuses 6 x x = 8.07 (corr to 2.d.p.) 42 ° x Cos 42  = x = 6 Cos 42 

19. Exercise 5  3 5 In the figure, find tan  tan  = adjacent Side Opposite side = 3 5  = 78.69  (corr to 2 d.p.)

20. Exercise 6 z 5 In the figure, find z tan 22  = adjacent Side Opposite side 5 z z = 12.38 (corr to 2 d.p.) 22  tan 22  = 5 tan 22  z =

21. Conclusion Make Sure that the triangle is right-angled

22. The END