What is the standard deviation of the following dataset: 12, 15, 18, 21?
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What is the maximum value of the function f(x) = x^3 - 2x^2 + 1 on the interval [0, 2]?
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Math question: Given triangle ABC, angle BAC is bisected by the angle bisector AD. If angle BAC measures 60 degrees, what is the measure of angle BAD and angle CAD?