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DeusAbscondus
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No matter how or what strategy I try, I can't get the optimum value for $x$ in the following equation:
$$V=4x^3-60x^2+200x$$ Let V=Volume of a rectangular prism, so:
$$V'=12x^2-60x+200$$ Set V'=0 to get turning point
$$12x^2-60x+200=0$$
The answer given in my text is when
$$ x=2.11 \Rightarrow \text{ the maximum volume is }\approx 192.45cm^2$$
I can graph it to get this, but can't get it using the quadratic formula for some reason.
some help would be appreciated
$$V=4x^3-60x^2+200x$$ Let V=Volume of a rectangular prism, so:
$$V'=12x^2-60x+200$$ Set V'=0 to get turning point
$$12x^2-60x+200=0$$
The answer given in my text is when
$$ x=2.11 \Rightarrow \text{ the maximum volume is }\approx 192.45cm^2$$
I can graph it to get this, but can't get it using the quadratic formula for some reason.
some help would be appreciated
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