\[ \boxed { {\frac {\rm d}{{\rm d}x}}y \left ( x \right ) =F \left ( y \left ( x \right ) {{\rm e}^{-bx}} \right ) {{\rm e}^{bx}}=0} \]
Mathematica: cpu = 24.434103 (sec), leaf count = 200 \[ \text {Solve}\left [\int _1^{y(x)} \left (\frac {1}{b K[2]-e^{b x} F\left (e^{-b x} K[2]\right )}-\int _1^x \left (\frac {F'\left (K[2] e^{-b K[1]}\right )}{e^{b K[1]} F\left (K[2] e^{-b K[1]}\right )-b K[2]}-\frac {e^{b K[1]} F\left (K[2] e^{-b K[1]}\right ) \left (F'\left (K[2] e^{-b K[1]}\right )-b\right )}{\left (e^{b K[1]} F\left (K[2] e^{-b K[1]}\right )-b K[2]\right )^2}\right ) \, dK[1]\right ) \, dK[2]+\int _1^x \frac {e^{b K[1]} F\left (y(x) e^{-b K[1]}\right )}{e^{b K[1]} F\left (y(x) e^{-b K[1]}\right )-b y(x)} \, dK[1]=c_1,y(x)\right ] \]
Maple: cpu = 0.047 (sec), leaf count = 31 \[ \left \{ y \left ( x \right ) ={\frac {{\it RootOf} \left ( -x+\int ^{{ \it \_Z}}\! \left ( F \left ( {\it \_a} \right ) -{\it \_a}\,b \right ) ^{ -1}{d{\it \_a}}+{\it \_C1} \right ) }{{{\rm e}^{-bx}}}} \right \} \]