Question 1142640
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You are given


    V(x) = 4x - x^2 = x*(4-x).


The roots of this parabola are x= 0 and x= 4 -- hence, the maximum of the parabola is half way between the roots, i.e. at x= 2.


It means that the maximum speed is (substitute x= 2 into the given formula)


    {{{V[max]}}} = 4*2 - 2^2 = 8 - 4 = 4 m/s.     <U>ANSWER</U>
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