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Math Help - More help with Quad functions

  1. #1
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    More help with Quad functions

    without graphing , whether the given quad function has a maximum or minimum value and then find it's value.

    Here's the problem

    f(x) = -2x^2+12x

    I tried completing the square, but it doesn't work.

    -2x^2 + 12x take 12/2+ 6 ^2 + 36 = (-2x^2+12x+36)

    Factor out -2(x^2-6x-18) and the problem doesn't factor from here. What am I missing?


    Thank You

    Jason
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  2. #2
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    What do you need completing the square for?

    a = -2, b = 12 now evaluate.

    Remember Min/Max is (\frac{-b}{2a},f\left(\frac{-b}{2a}\right))

    You don't need to factor.
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  3. #3
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    Thanks again.
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