Now, equation (1) is first order linear differential equation
We know that solution of first order linear differential equation is given by
where,
Now, solving equation(2) by using I.F.
Now, using y(1)= 1 in equation (3)
Now, putting value of c in equation (3)
Hence, solution of given differential equation is
A large tank is partially filled with 100 gallons of fluid in which 10 pounds of
salt is dissolved. Brine containing ½ pound of salt per gallon is pumped into
the tank at a rate of 6 gal/min. The well-mixed solution is then pumped out
at a slower rate of 4 gal/min. Find the number of pounds of salt in the tank
after 30 minutes.