1. The problem statement, all variables and given/known data Find the differential equation of ln y = ax^2 + bx + c by eliminating the arbitrary constants a, b and c. 2. Relevant equations Wrosnkian determinant. 3. The attempt at a solution I've solved a similar problem (y=ax^2+bx+c --> y'''=0), but couldn't do the same with this one. All what I could is taking the exponent of both sides --> y=e^(ax^2 + bx + c).