A factory is dumping garbage into a river at a rate given by dx
dt =et
200 tons per month,
where t is the time in months since the dumping began and x is the number of tons of
garbage. Find the function x(t) which gives the total number of tons of garbage dumped.
Determine:
2
2
3x
x2– 1 dx
A company has determined that its marginal revenue function (in dollars) is given by
R’(x) = 10,000 –x2, where x is the number of units sold. Find the total revenue for selling 4
units by finding the area in the first quadrant bounded by y=R’(x) = 10,000 –x2 and the
lines y= 0, x= 0, and x= 4.
Use differentials and R= 300x+ 50x2–x3 to approximate the change in revenue R (in
dollars) from selling x pounds if the number of pounds increases from 10 to 10.2.
The supply equation for a certain radio is given by p= 0.8 x+ 17 where p is the price in
dollars and x is the number of radios supplied. Use differentials to approximate the price
when 620 radios are supplied. (Hint: Use x = 625.)
The income (in dollars) from a clothing store is increasing at a rate of f(t) = 500e0.08t where
t is in weeks. Find
12
6
500e0.08tdt, the total income for the store between the sixth and
twelfth weeks.
For the region bounded by f(x) = 4 –x, y= 0, x= 0, and x= 3, approximate the area by
evaluating S6. (Use the left–hand endpoint of each subinterval.)