A tank of liquid has both an inlet pipe allowing liquid to be added to the tank and a drain allowing liquid to be drained from the tank.
The rate at which liquid is entering the tank through the inlet pipe is modeled by the function i(x)=3x^2+2, where the rate is measured in gallons per hour. The rate at which liquid is being drained from the tank is modeled by the function d(x)=4x−1 where the rate is measured in gallons per hour.
What does (i−d)(3) mean in this situation?
+235 Since i is how much liquid is being put in, and d is how much is being let out, i - d is how much liquid is in the container at any given time. So (i-d)(3) is how much liquid is in the container in gallons after three hours.
Hope this helps!
+129850 (i - d) is the rate the tank is being filled after x hours
For instance....after 2 hours the tank is being filled at 3(2)^2 + 2 = 14 gal/hr
And it is being drained at 4(2) - 1 = 7 gal/hr
So.....the net is that it is being filled at 2 hours = 14 - 7 = 7 gals/hr
So
(i - d)(3) is the rate that the tank is being filled at 3 hrs
The rate at which the amount of liquid in the tank is changing at t = 3 hours is 18 gallons per hour.
The rate at which the amount of liquid in the tank is changing at t = 3 hours is 40 gallons per hour.
There are 40 gallons of liquid in the tank at t = 3 hours.
There are 18 gallons of liquid in the tank at t = 3 hours.
those are my answer choices
