Question 1135305
if the function is negative when (3 < x < n), then 3 and n must be zeroes of the function.


if we assume that 3 is one of the zeroes, then f(3) must be equal to 0.


when x = 3, the equation becomes 2 * 3^2 + m * 3 + 27 = 0


this then becomes 18 + 3m + 27 = 0 which becomes 3m + 45 = 0 which results in m = -15.


the equation becomes 2x^2 - 15x + 27 = 0.


factor this equation to get (2x - 9) * (x - 3) = 0


solve for x to get x = 3 or x = 4.5.


you get m = -15 and n = 4.5.


here's the graph.


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