1. cotx= (quotient identity)

2. Answer

3. sinxcosx=

4. Answer

5. tan(x/2)= (half angle identity)

6. Answer

7. tan(x+y)= (sum identity)

8. Answer

9. sin(x+y)= (sum identity)

10. =sinxcosy+sinycosx Answer

11. cos(2x)= (double angle identity)

12. =cos 2 x-sin 2 x (main-others are found using Pythagorean Identities) =2cos 2 x-1 =1-2sin 2 x Answer

13. sin(x/2)= (half angle identity)

14. Answer

15. sinx= (reciprocal identity)

16. Answer

17. cot 2 x= (Pythagorean identity)

18. =csc 2 x-1 Answer

19. tanx= (reciprocal identity)

20. Answer

21. cos(x+y)= (sum identity)

22. =cosxcosy-sinxsiny Answer

23. sin(x-y)= (difference identity)

24. =sinxcosy-sinycosx Answer

25. sin 2 x= (Pythagorean identity)

26. =1-cos 2 x Answer

27. cos(x/2)= (half angle identity)

28. Answer

29. tanx= (quotient identity)

30. Answer

31. tan 2 x+1= (Pythagorean identity)

32. =sec 2 x Answer

33. tan(2a)= (double angle identity)

34. Answer

35. cos(x-y)= (difference identity)

36. =cosxcosy+sinxsiny Answer

37. sin(2x)= (double angle identity)

38. =2sinxcosx Answer

39. tan(x-y)= (difference identity)

40. Answer

41. cosx= (reciprocal identity)

42. Answer