Explain how special right triangles, reference angles, and quadrants of a coordinate grid help us find the exact answer to the following: cos 210°.
There were no graphs
Do you know the unit circle?
No but I think I'm just trying to explain how to use those methods to find the answer.
fine then 1. Know that cos is the x coordinate 2. tell me which quadrant 210 degrees falls in
cos(0) is in Q1?
210 degrees e.e starting from the coordinate (1,0) which means that it's in the third quadrant, 30 degrees in agreed?
so it's like here |dw:1623973191797:dw| the reference angle is 30 degrees
so then what about the special right triangles?
|dw:1623973432055:dw| do you see the triangle? fin dx
Yeah, so how would I put all of this into words?
draw on it a unit circle, you find out you can draw a right triangle in the third quadrant, then use one of hte trig ratios to find x
I can't respond using images just text. So I'm trying to figure out how to describe these features in words. Thank you!
just describe the circle and the angles -- have fun --- and yw~
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