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Use the calculus you know to find the value of x that maximizes this expression. Harley
Hi Chris. A second way to solve the problem is to use your knowledge of parabolas rather than calculus.
is a quadratic equation. If you multiply this out and turn it into the y = a(x  p) + q "vertex graphing" form, then you can quickly determine the vertex of the equation. Since "a" is negative in your case, this is a parabola opening downwards ("concave down"). So the maximum y value occurs at the vertex. Steve La Rocque.  


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