\[ y'(x)=\frac {x F\left (\frac {y(x)^2-b}{x^2}\right )}{y(x)} \] ✓ Mathematica : cpu = 0.373226 (sec), leaf count = 236
DSolve[Derivative[1][y][x] == (x*F[(-b + y[x]^2)/x^2])/y[x],y[x],x]
\[\text {Solve}\left [\int _1^{y(x)}\left (-\frac {K[2]}{-F\left (\frac {K[2]^2-b}{x^2}\right ) x^2+K[2]^2-b}-\int _1^x\left (\frac {F\left (\frac {K[2]^2-b}{K[1]^2}\right ) K[1] \left (2 K[2] F'\left (\frac {K[2]^2-b}{K[1]^2}\right )-2 K[2]\right )}{\left (F\left (\frac {K[2]^2-b}{K[1]^2}\right ) K[1]^2-K[2]^2+b\right )^2}-\frac {2 K[2] F'\left (\frac {K[2]^2-b}{K[1]^2}\right )}{K[1] \left (F\left (\frac {K[2]^2-b}{K[1]^2}\right ) K[1]^2-K[2]^2+b\right )}\right )dK[1]\right )dK[2]+\int _1^x-\frac {F\left (\frac {y(x)^2-b}{K[1]^2}\right ) K[1]}{F\left (\frac {y(x)^2-b}{K[1]^2}\right ) K[1]^2-y(x)^2+b}dK[1]=c_1,y(x)\right ]\] ✓ Maple : cpu = 0.14 (sec), leaf count = 67
dsolve(diff(y(x),x) = F(-(-y(x)^2+b)/x^2)*x/y(x),y(x))
\[y \left (x \right ) = \sqrt {\RootOf \left (-2 \ln \left (x \right )+\int _{}^{\textit {\_Z}}\frac {1}{F \left (\textit {\_a} \right )-\textit {\_a}}d \textit {\_a} +2 c_{1}\right ) x^{2}+b}\]