1. The problem statement, all variables and given/known data yy''+(y')2 = 0 2. Relevant equations yv(dv/dy)+v2=0 3. The attempt at a solution Variable separable when solving for the first step the result is: - ln |v| = ln |y| + C1 Now, I've looked at the remainder of the solution with a few other sources and the cause of my mistake results in the constant. After turning the equation into: ln |vy| + C1 = 0; I raise everything to the e so that I can solve for v. It seems all the solutions do that as well but yet they don't raise the constant to the e. Is it because eC1 will still be a constant and therefore completely arbitrary?