Question

What is sin Pi/4 in a unit circle?

Answer 1

please help!

Answer 2

use this unit circle

http://www.regentsprep.org/Regents/math/algtrig/ATT5/600px-Unit_circle_angles_svg.jpg

locate the angle pi/4

then find the corresponding point on the unit circle for angle pi/4

what is the y coordinate of that point?

Answer 3

is it 45 degrees?

Answer 4

45 degrees = pi/4 radians

the final answer isn't 45 degrees though

Answer 5

i'm not sure what to do after then....

Answer 6

look at the attached image

notice how I'm circling the point when the angle is pi/4

Answer 7

what point did I circle?
what is the y coordinate of that point?

Answer 8

sqrt 2/2?

Answer 9

therefore,

\[\Large \sin\left(\frac{\pi}{4}\right) = \frac{\sqrt{2}}{2}\]

Answer 10

the y coordinate corresponds to sine
the x coordinate corresponds to cosine

Answer 11

so the answer is Pi/4?

Answer 12

the answer is 1/root2

Answer 13

sorry, i meant sqrt 2

Answer 14

Another example,

\[\Large \sin\left(\frac{\pi}{3}\right) = \frac{\sqrt{3}}{2}\]

Answer 15

i understood, i just typed the wrong thing that iwas trying to say. but thank you!

Answer 16

no problem