Find the absolute maximum and absolute minimum values of `f(x)=4x-(x^2)/2` in `[-2,\ 4. 5]`

Explanation

`f(x)=4x-(x^2)/2`

`f prime (x)= 4-x`

for critical points `f prime (x) =0`


`4-x=0`

`x=4`

`f(-2)=4(-2)-(-2^2)/2`

`f(-2)=-8-2=-10`

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