#need help on finding the x and y coordinates on a unit circle

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finite fog
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in this video he uses the properties of special right triangles to find the x and y coordinates of an angle on the unit circle but isn't the hypotenuse supposed to be 1 and then you solve from there? Here is how I did it by setting the hypotenuse to 1 (I will send through phone the picture will be in chat. Also for unit circles is cosine and sine assocaited with x and y because they are over 1 because of the hyptonuse being 1 so its just the lenght of the base and height?

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olive boneBOT
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finite fog
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Here is my photo

hollow orbit
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the 30-60-90 special right triangle has a hyp. length of 2, adj. length of √3 and opp. length of 1! he uses another way to find the 'special angles' of sine, cosine and tangent, where, say you were to evaluate sin(30°) , you can use the 30-60-90 special right triangle, and knowing 30° is in quadrant 1 of the unit circle, then the x, y values are pos., so the opp is +1 , adj is +√3 and hyp is +2, sin 30 = opp/hyp = 1/2

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if you took sin(150°), the angle is in quadrant 2, and its reference angle is 180° - theta since its in quadrant 2

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or in this case, 180° - 150°

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which is 30°

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so this is another case where you can use the 30-60-90 special right triangle

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but in Q2 the x value is negative

hollow orbit
finite fog
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oh I see thank you

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