Question: In triangle ABC, angle BAC measures 60 degrees. If the angle bisector of angle BAC intersects side BC at point D, and AD measures 10 cm, what is the length of DC?
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Find the equation of a hyperbola with foci at (-3,0) and (3,0), and the distance between any point on the hyperbola and its corresponding directrix is 5.
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What is the limit of f(x) as x approaches 2, if f(x) = (3x^2 - 2x + 1) / (x^2 - 4)?