anonymous one year ago medal award!

1. anonymous

2. Mertsj

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3. Mertsj

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4. anonymous

I don't really understand what is what..

5. Mertsj

It's learning the unit circle I think with emphasis on the angles of the special right triangles.

6. anonymous

if i'm not mistaken the two distances than are 5pi/4 and pi/4?

7. Mertsj

$\sin \frac{\pi}{4}=\cos \frac{\pi}{4}=\frac{\sqrt{2}}{2}$

8. Mertsj

So whenever you have a reference angle of pi/4, the sin and cos will be sqrt2/2 making adjustment for the sign depending on the quadrant.

9. Mertsj

So if the cos, which is like x, is -sqrt2/2, you must be in either quadrant 2 or 3 and the reference angle must be pi/4

10. Mertsj

And so the distance on the unit circle would be pi-pi/4 and pi + pi/4 or 3pi/4 and 5pi/4

11. anonymous

but speficially for this problem when it refers to the distances they just want (sqrt(2)/2,sqrt(2)/2)?

12. Mertsj

No. They want the distance traveled on the unit circle.

13. Mertsj

Or in other words, they want the angle

14. anonymous

I put in 5pi/4 and 3pi/4 it said it's incorrect

15. Mertsj

Well then it must be a formatting problem because if the x value is -sqrt2/2, the angles are 3pi/4 and 5pi/4

16. Mertsj

did you put in the comma?

17. anonymous

i put in 3pi/4, 5pi/4

18. anonymous

it's right! I probably forgot to add in the comma the first time :) thank you

19. Mertsj

yw

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