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May 6th, 2013, 02:56 AM   #1
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Points on unit circle

Hello.

Find the point P(t) on the unit circle for the values below:







is on the same spot as , in QI.





This means is a third between and .
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May 6th, 2013, 05:30 PM   #2
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Re: Points on unit circle



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May 6th, 2013, 07:40 PM   #3
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Re: Points on unit circle

Quote:
Originally Posted by greg1313


I'm guessing the ? + ?/4 has something to with the reference angle, although I'm not sure exactly what?!
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May 7th, 2013, 02:11 AM   #4
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Re: Points on unit circle

79 is an odd number, so we complete thirty-nine and one-half rotations on the unit circle. This leaves us at pi, then we add a quarter.
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May 7th, 2013, 02:46 AM   #5
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Re: Points on unit circle

I think I'm getting it. The 317 frightened me.

Since 317 is odd and the radian measure is ?/4, we simply start at ?. And since 317?/4 is positive it goes in the counterclockwise direction from ?, ?/4 units to give 5?/4.

Quote:
Originally Posted by greg1313
79 is an odd number, so we complete thirty-nine and one-half rotations on the unit circle. This leaves us at pi, then we add a quarter.
Do you mean seventy-nine instead of thirty-nine?
Where did the 79 come from?
It isn't a factor of 317; I'm guessing that you chose it randomly because it is odd?!
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May 7th, 2013, 03:00 AM   #6
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Re: Points on unit circle

317/4 = 79 + 1/4. This is a factor of pi. Dividing 79 by 2 we obtain 39 complete rotations around the unit circle, with a remainder of 1/2. This leaves us at pi. Then we add 1/4.

For clarification, consider 2?. It is one complete rotation around the unit circle.
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May 7th, 2013, 03:28 AM   #7
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Re: Points on unit circle

Quote:
Originally Posted by Aftermath
Since 317 is odd and the radian measure is ?/4, we simply start at ?. And since 317?/4 is positive it goes in the counterclockwise direction from ?, ?/4 units to give 5?/4.
Try 319?/4.
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May 9th, 2013, 11:15 AM   #8
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Re: Points on unit circle

Quote:
Originally Posted by greg1313
Quote:
Originally Posted by Aftermath
Since 317 is odd and the radian measure is ?/4, we simply start at ?. And since 317?/4 is positive it goes in the counterclockwise direction from ?, ?/4 units to give 5?/4.
Try 319?/4.
Sorry for the delay in reply. Thanks for your responses so far!

319/4 is 79 + 3/4. From this we are going around the circle 39 and a half times. Landing back on ?. Now add the 3/4 to get 7?/4.



I got the point about 2? as it relates to 39. 79? is the same as 2(39?).
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May 9th, 2013, 11:24 AM   #9
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Re: Points on unit circle

Quote:
Originally Posted by Aftermath
319/4 is 79 + 3/4. From this we are going around the circle 39 and a half times. Landing back on ?. Now add the 3/4 to get 7?/4.



Quote:
Originally Posted by Aftermath
79? is the same as 2(39?).
Are you sure about that?
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May 9th, 2013, 12:27 PM   #10
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Re: Points on unit circle

Quote:
Originally Posted by greg1313
Quote:
Originally Posted by Aftermath
319/4 is 79 + 3/4. From this we are going around the circle 39 and a half times. Landing back on ?. Now add the 3/4 to get 7?/4.



Quote:
Originally Posted by greg1313
Quote:
Originally Posted by Aftermath
79? is the same as 2(39?).
Are you sure about that?
I'm wrong. 79? is the same as 2(39.5?)

Thank you very much for your patient help!
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