

so the ODE is indeed exact and there is a solution of the form
. We have




With
, we have

so

7.5 xxx. 8.0 xxx 8.5 xxx 9.0 xxxxx 9.5 xxxx
the answer for this question is 64-144a+108a^2-27a^3
The difference would be subtracting the variables and the dividing the difference by 2