## nikakuz Group Title Name five x values for which the sine function equals to 0. Please help!! one year ago one year ago

1. Mertsj Group Title

Are you familiar with the unit circle?

2. nikakuz Group Title

no

3. Mertsj Group Title

Then find the inverse sine of 0 and and 360 to that answer repeatedly until you have 5 values.

4. nikakuz Group Title

how?

5. Mertsj Group Title

6. nikakuz Group Title

I don't know how though

7. Mertsj Group Title

inverse sin 0 enter

8. Mertsj Group Title

What in the world are you doing that you don't know anything about the unit circle and don't know how to use your calculator?

9. nikakuz Group Title

i put sin 0 enter and the answer was 0 how do i get 5 values?

10. nikakuz Group Title

trying to learn from an oonline classs

11. Mertsj Group Title

|dw:1375670932781:dw|

12. Mertsj Group Title

Have you ever seen that before?

13. nikakuz Group Title

yeah

14. Mertsj Group Title

That is the unit circle. It is called the unit circle because the radius is 1 unit. The sin is like y.

15. Mertsj Group Title

Do you see that the y value is 0 at 0 degrees and 180 degrees?

16. nikakuz Group Title

yes

17. Mertsj Group Title

Your problem says to give 5 values for which the sin is 0. There are two of them right there: 0 degrees and 180 degrees. If we would go around the circle another time, we would come to 360 degrees and 180+360 which is 540 degrees. Are you with me?

18. nikakuz Group Title

sorta.. so it would be 0,180,540?

19. Mertsj Group Title

0,180,360,540... Just keep adding 180 degrees because every 180 degrees, the y value (which is the sin) is 0.

20. Mertsj Group Title

Or, instead of rotating counterclockwise, we could go clockwise and then the angles would be -180, -360, -540, ...

21. nikakuz Group Title

ohh ok thank you! i have the same question exept its cosine value

22. Mertsj Group Title

Same thing except the cosine is like x.

23. Mertsj Group Title

So where is the cosine 0 on the unit circle?

24. nikakuz Group Title

um im not sure

25. Mertsj Group Title

Look at the picture I drew. For what angles is the x value 0?

26. Mertsj Group Title

|dw:1375671563924:dw|

27. Mertsj Group Title

How many degrees is that?

28. nikakuz Group Title

90?

29. Mertsj Group Title

Yes.

30. Mertsj Group Title

And what is the next angle where the x value is 0?

31. nikakuz Group Title

so it would be 90 180...?

32. Mertsj Group Title

|dw:1375671659091:dw|

33. nikakuz Group Title

270?

34. Mertsj Group Title

yes. so the x value is 0 at 90, 270, 450, 630...

35. nikakuz Group Title

thank you soo much i just have one more

36. Mertsj Group Title

Or at -90, -270, -450...

37. nikakuz Group Title

same but tangent function

38. Mertsj Group Title

Do you know the definition of tangent?

39. nikakuz Group Title

umm no

40. Mertsj Group Title

tangent is equal to sin over cos Have you ever heard that?

41. nikakuz Group Title

i think ive heard it

42. Mertsj Group Title

$\tan x=\frac{ \sin x}{\cos x}$

43. Mertsj Group Title

The only way a fraction can be 0 is for the numerator to be 0. So the tangent is 0 whenever the sin is 0

44. nikakuz Group Title

ok so then wht

45. Mertsj Group Title

Are you trying to answer this question: Give 5 angles who tangent is 0?

46. nikakuz Group Title

the question is name five x values for which the tangent function equals to 0

47. Mertsj Group Title

Could you answer this question: Name five x values for which the sine function equals to 0?

48. nikakuz Group Title

yeah we already did that one

49. Mertsj Group Title

So did you read this post which I made a few moments ago: "The only way a fraction can be 0 is for the numerator to be 0. So the tangent is 0 whenever the sin is 0"

50. nikakuz Group Title

yeah i read it but i don't understand

51. Mertsj Group Title

The sin of 180 degrees is 0. Therefore the tangent of 180 degrees is also 0 The sin of 0 degrees is 0. Therefore the tangent of 0 degrees is also 0 The sin of 360 degrees is 0. Therefore the tangent of 360 degrees is also 0 The sin of 540 degrees is 0. Therefore the tangent of 540 degrees is also 0.

52. nikakuz Group Title

so my answer would be exactly the same as the sine one?

53. Mertsj Group Title

Let's make sure you understand this.

54. Mertsj Group Title

What is the sin of 180 degrees?

55. nikakuz Group Title

0

56. Mertsj Group Title

What is the cosine of 180 degrees?

57. Mertsj Group Title

$\tan 180^{o}=\frac{\sin 180^{o}}{\cos 180^{o}}=\frac{0}{-1}=0$

58. Mertsj Group Title

I guess you've gone. Good luck.

59. nikakuz Group Title

yeah i get it thank you soo much!!!!