# math

evaluate (sin 30°-sin60°)/tan60°

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1. recall that
sin30° = 1/2
sin60° = cos30° = √3/2
(sin^2+cos^2 = 1)
tan60° = cot30° = cos30°/sin30° = √3

recall that co-f(x) = f(90°-x)
That is, the co-function is the function of the complement!

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oobleck

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