Help, please! On a Unit Circle, how do you know which angle to reference (90 degrees, 180 degrees, 270 degrees, or 360 degrees) when finding the sine, cosine, and tangent, etc, of a certain angle. I know this is a bit confusing but I can clarify! Medal to anyone who answers!

Question

freckles · Answer

hey I'm not totally sure what you are asking
can you give an example

lina777 · Answer

@freckles Hey, sorry! So for example, if I was to say, give the reference angle for theta=2pi/3, which is equal to 120, how would I know if I needed to go up to 180 to subtract 180-120 to get a reference angle of 60, or go down, and say that 120-90=30, and get a reference angle of 30. Do you see what I am saying?

directrix · Answer

@lina777 

One side of the terminal angle must be on the x axis.

directrix · Answer

For 120 degrees

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