xy''=y'ln(y'/x)x(y''/y')=ln(y'/x)x(lny')'=lny'-lnxlny'=pxp'=p-lnxxdp=pdx-lnxdxp/x=udp=xdu+udx x^2du+xudx=xudx-lnxdxx^2du=-lnxdxdu=-lnxdx/x^2u=∫-lnxdx/x^2=∫lnxd(1/x)=lnx/x-∫dx/x^2=lnx/x+1/x+C0p=lnx+...