What is the product of the sum of x and y, squared, when x = 3 and y = 5?
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What is the equation of a parabola if the coefficient a is negative and the vertex is at (1, 4)?
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What is the end behavior of the cubic function f(x) = x^3? Does it approach positive infinity as x approaches positive infinity? Does it approach negative infinity as x approaches negative infinity? Justify your answer.