SOHCAHTOASOHCAHTOA recalls right-triangle ratios: Sine = Opposite/Hypotenuse, Cosine = Adjacent/Hypotenuse, Tangent = Opposite/Adjacent. Use a chosen acute angle, between 0° and 90°.
You’ll leave with these skills
01Set Desmos to degree or radian mode to match the question’s angleMatch the mode to the angle’s unit: degree mode for degrees and radian mode for radians. A degree symbol or an explicit unit takes priority over whether the number contains π.
02Find an angle of a right triangle from two of its sidesType arcsin, arccos, or arctan of the two sides’ ratio in degree mode to get the angle in degrees.
03Find the sine or cosine of an angle measured in radiansFor an angle measured in radians, use radian mode and evaluate the sine or cosine. Compare choices at the precision displayed by the calculator; an unlabeled trigonometric argument conventionally uses radians.
04Turn one given trig ratio into anotherType the given ratio inside arccos or arcsin, wrap that in sin or cos, and pick the answer choice whose decimal matches.
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