I think you multiply rong
That is the slope at f(1)
one way is to just take the derivitive
f'(x)=2x+(1/x)
for ti-89, do calc then derivitive then input "x^2+ln(x),x)" and click enter to get the derivitive
you would get f'(x)=2x+(1/x)
an easier way would be to have
click calc then differntiate then type x^2+ln(x),x)|x=1 then click enter
you get f'(1)=3
answer is 3
The rate would be 75 miles in 1 hour.
Set up a proportion to solve this:
3 1/8 miles in 2.5 minutes gives us the ratio 3.125/2.5.
The second ratio would be x miles in 60 minutes, or x/60.
3.125/2.5 = x/60
Cross multiply:
187.5 = 2.5x
Divide both sides by 2.5:
187.5/2.5 = 2.5x/2.5
75=x
Answer: 3x^2 +120x
Good luck !