Question 1193035
graph it.
{{{graph(300,300,-10,5,-500,10,(-100e^(-0.25x)-50x))}}}
f'(x)=0.25*e^(-0.25x)-50
set equal to 0.
50=25e^(-0.25x)
2=e^(-0.25x)
ln 2=-0.25x
0.693=-0.25x
x=-2.77
f(x)=-61.37
second derivative is -6.25e^(-0.25x)
where x=-2.77 the second derivative is negative. This is a maximum.