Fuel consumption of a new car was measured when it was test driven at various speeds in top gear. For a speed of 'v' kilometres per hour, the fuel consumption, f(v) kilometers per litre, was found to be roughly modelled, for 50
f(v) = -0.0019v^2 + 0.3686v + 8
a) Find f(v) and df/dv when v = 70 and 100.
b) What do the results in (a) indicate about fuel economy?
c) What is the most economical speed for this car?
2007-02-05 12:43:48 · 1 answers · asked by m577a1 1 in Science & Mathematics ➔ Mathematics
f(70) = 24.492 and f(100) = 25.86
f'(v) = -.0038v+.3686
f'(70) =.1026 and f'(100) = - .0114
Fuel consumption is best at 97 km/hour (.3686/.0038)
Fuel consuption gets better and better until it maxes at v = 97 then strat getting wors as the derivative goes negative.
2007-02-05 13:08:19 · answer #1 · answered by ironduke8159 7 · 0⤊ 0⤋