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 ??

Answer 1

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

Answer 2

yup

Answer 3

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

Answer 4

@mattt9

Answer 5

and what was your derivative again?

Answer 6

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

Answer 7

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

Answer 8

yeah explain that please

Answer 9

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