sandy524 Group Title Find the derivative of f when f(x) = 2 tan(x) + 3 cot(x) one year ago one year ago

1. cwrw238 Group Title

derivative of tan x is sec^x can't remember derivative of cot x - try googling it first term of derivative is 2 sec^2 x

2. sandy524 Group Title

of cotx? its -csc^2

3. cwrw238 Group Title

4. sandy524 Group Title

sol: let y=f(x) y=2tan(x)+3cot(x) =2dy/dxtanx+3dy/dxcotx =2*sec^2x+3*-cosec^2x =2sec^2x-3cosec^2x

6. cwrw238 Group Title

oh ok so f'(x) = 2 sec^2 x - 3 csc^2 x

7. sandy524 Group Title

think they want me to make in ration form its number 3 on the hw i have attached

9. sandy524 Group Title

thats not one of the answer choices

10. sandy524 Group Title

11. sandy524 Group Title

are these questions???

13. sandy524 Group Title

yes the document i have attached is the homework i am looking at number 3 specifically

14. cwrw238 Group Title

ah what they have done is convert the sec and csc to sin and cos

15. sandy524 Group Title

okay...

16. sandy524 Group Title

17. cwrw238 Group Title

2 sec^2 x - 3 csc^2 x = 2 * 1/cos^2 x - 3 * 1 / sin^2 x

18. cwrw238 Group Title

|dw:1350060084696:dw|

19. sandy524 Group Title

20. sandy524 Group Title

21. sandy524 Group Title

i have to turn it on in ten minutes

22. cwrw238 Group Title

well i think it is the answer but its in different form to your choices - i'm trying to figure it out

23. swissgirl Group Title

2sec^2(x)-3csc^2(x)?

24. cwrw238 Group Title

yes - do you agree with that answer?

25. sandy524 Group Title

the answer choices r on the document

26. sandy524 Group Title

27. sandy524 Group Title

have attached the hw

28. sandy524 Group Title

the answer choice are on the paper

29. cwrw238 Group Title

i know that sandy - but i can't figure out which is equivalent to the sec and csc expression

30. swissgirl Group Title

hmm maybe you need to get a common deonmanator

31. sandy524 Group Title

:(

32. sandy524 Group Title

33. sandy524 Group Title

34. sandy524 Group Title

due in four minutes

35. sandy524 Group Title

36. sandy524 Group Title

i dont need an explainatio just the answer

37. sandy524 Group Title

nvm the hw is past due now :(

38. cwrw238 Group Title

there might be a mistake in the paper i'm sure 2sec^2x - 3 csc^2 x is correct but u need to convert it

39. sandy524 Group Title

smh wow

40. cwrw238 Group Title

hold on - i think I've got it

41. sandy524 Group Title

its too late

42. sandy524 Group Title

thank u anyways

43. swissgirl Group Title

ohhh I got the answer $$\large {2-5\cos^2(x) \over \sin^2(x)\cos^2(x)}$$

44. cwrw238 Group Title

yes - i've converted the to sines and cosines but i can't get any of the choices on the paper yes - i got that - but its not one of the choices

45. swissgirl Group Title

its the fourth choice

46. cwrw238 Group Title

oh - i've been looking in the wrong place!!!!!

47. swissgirl Group Title

hahah I know its quite confusing to follow

48. cwrw238 Group Title

lol