## anonymous 4 years ago I need help I will download question

1. anonymous

@mayankdevnani

2. anonymous

3. anonymous

4. anonymous

Do you know the trigonometric identities? Sin and cosine?

5. anonymous

6. anonymous

|dw:1349573615545:dw|

7. anonymous

cos 50=x/90

8. anonymous

Not so fast. So we know that $$a=50$$ degrees. $$\cos a=\frac BC$$. $$C$$ we know is $$90$$. So yes, to solve for B, you would use $$B=90\cos a$$.

9. anonymous

cost 50=confused

10. anonymous

cos 50=x/90

11. anonymous

Yes. Multiply both sides by $$90$$.

12. anonymous

you multiply 50x90 right

13. anonymous

No, you multiply 90 by cos 50.

14. anonymous

50x90=4,500

15. anonymous

i got 4,500

16. anonymous

$90\cdot\cos50\neq90\cdot50$

17. anonymous

i got 86.87

18. anonymous

That sounds off.

19. anonymous

im not sure

20. anonymous

Do you know how to do $$90\times\cos50$$?

21. anonymous

cosx50 right

22. anonymous

No, $$\cos$$ is an operation.

23. anonymous

im getting 4,500 for some reason

24. anonymous

Alright, do you know what an operation is? $$\sin x$$ and $$\cos x$$ are like machines into which you put a number $$x$$ and retrieve a value. So do $$\cos50$$ first.

25. anonymous

im getting 50

26. anonymous

i did cos 50

27. anonymous

if i do 50 cos=0.9649

28. anonymous

$$50\cos\neq\cos50$$.

29. anonymous

It's not a multiplication.

30. anonymous

im getting 50

31. anonymous

i click on cos and than i put 50 so i got 50

32. anonymous

I have no idea what you're talking about. You sound confused. Do you know what $$\sin x$$ is?

33. anonymous

yes on calculator

34. anonymous

No, even more importantly, $$\sin x$$ is an operation performed on $$x$$. You're used to operations like $$+,-,\times,\div$$, but $$\sin x$$ is an operation like that. You can't just move the $$\sin$$ around.

35. anonymous

@swissgirl @bahrom7893 I can't tell what the confusion here is. Help me!

36. anonymous

@nincompoop You are a better teacher.

37. anonymous

Ok well on your calculator you should have this button called sin, cos and tan correct?

38. anonymous

yes

39. anonymous

allrrighhttyy so on your calculator type 90*Cos(50) then press enter

40. anonymous

ohhhh u r on radians. You gotta set your calculator to degrees

41. anonymous

oh that's the problem

42. anonymous

i dont know why im getting 4,500

43. anonymous

what i did is 90xcos50

44. anonymous

you don't multiply when its cos(50) right

45. anonymous

90*50=4500 But we are typing 90*Cos(50) remember to include the Cos

46. anonymous

ok i was using my iphone calculator that's why it wasnt working now im using internet cal and i got57.85

47. anonymous

Correct:)

48. anonymous

so what's next

49. anonymous

50. anonymous

51. anonymous

The cosine of a 50° angle is ____

52. anonymous

@lgbasallote YOU.

53. anonymous

The second most powerful. Most powerful is undoubtedly CleverBot. :P

54. anonymous

Unfortunately, CleverBot is not programmed to give you right answers. Just data mine a lot.

55. anonymous

ok who i should ask for help

56. anonymous

Ugh, I don't know how to help because it seems you aren't clear about what you're confused on.

57. anonymous

ok

58. anonymous

i wasnt using the right calculator

59. anonymous

now i got it

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