help help help!!!! Determine the extrema of f(x)= (-4)* x/ x^2+7 below on the given interval

(a) on [1,4]
The minimum is ?? and the maximum is ??
(b) on [1,5]
The minimum is ?? and the maximum is ??

Question

help help help!!!! Determine the extrema of  f(x)= (-4)* x/ x^2+7 below on the given interval

(a) on [1,4]
The minimum is ?? and the maximum is ??
(b) on [1,5] 
The minimum is ??  and the maximum is ??

anonymous · Answer

is the x^2+7 all under the -4x

anonymous · Answer

yup

anonymous · Answer

yup$$ \frac{ (-4)*x}{ x^{2}+7}$$

anonymous · Answer

@mattt9

anonymous · Answer

and what was your derivative again?

anonymous · Answer

$$\frac{ 1*(x ^{2}+ 7)-2x(-4)*x}{ (x^{2}+7) ^2 }$$

anonymous · Answer

are you sure that is correct wouldn't the derivative of the top be -4 not 1

anonymous · Answer

yeah explain that please

anonymous · Answer

maybe I did get it wrong. but i assumed since -4 is a constant i didn't use it...

anonymous · Answer

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