What is the equation of an ellipse with its major axis being vertical, center at (2,-3), a major axis length of 6 units, and a minor axis length of 4 units?
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What is the length of side c in a triangle if sides a and b have lengths 5 and 8, and angle C is 60 degrees?
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What is the limit of f(x) as x approaches 2, if f(x)=3x^2-4x+5?