\[ y'(x)=\frac {e^{b x}}{e^{-b x} y(x)+1} \] ✓ Mathematica : cpu = 0.501585 (sec), leaf count = 101
\[\text {Solve}\left [\frac {1}{2} b \left (\log \left (-b e^{-2 b x} y(x)^2-b e^{-b x} y(x)+1\right )+2 b x\right )=\frac {b \tan ^{-1}\left (\frac {(b+2) \left (-e^{b x}\right )-b y(x)}{b \sqrt {-\frac {b+4}{b}} \left (e^{b x}+y(x)\right )}\right )}{\sqrt {-\frac {b+4}{b}}}+c_1,y(x)\right ]\] ✓ Maple : cpu = 0.386 (sec), leaf count = 98
\[\left \{y \left (x \right ) = \RootOf \left (\textit {\_Z}^{2} b +\textit {\_Z} b -{\mathrm e}^{\RootOf \left (b \left (\tanh ^{2}\left (\frac {\sqrt {b^{2}+4 b}\, \left (-2 b x +2 c_{1} b -\textit {\_Z} \right )}{2 b}\right )\right )+4 \left (\tanh ^{2}\left (\frac {\sqrt {b^{2}+4 b}\, \left (-2 b x +2 c_{1} b -\textit {\_Z} \right )}{2 b}\right )\right )-b -4 \,{\mathrm e}^{\textit {\_Z}}-4\right )}-1\right ) {\mathrm e}^{b x}\right \}\]