What is the median of the set {4, 7, 2, 9, 1, 6, 3}?
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Find the value of sinh(arccosh((sinh^2(pi/4) + cosh^2(pi/3))/tanh(2.5))), where sinh is the hyperbolic sine function, and arccosh is the inverse hyperbolic cosine function.
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What is the derivative of f(x) = sin^2(x) + tan(2x) - 3cos(x) + sec^2(x) at x = π/4?