\[ \boxed { {\frac {\rm d}{{\rm d}x}}y \left ( x \right ) -f \left ( x \right ) \left ( y \left ( x \right ) \right ) ^{a}-g \left ( x \right ) \left ( y \left ( x \right ) \right ) ^{b}=0} \]
Mathematica: cpu = 2.267788 (sec), leaf count = 27 \[ \text {DSolve}\left [-f(x) y(x)^a-g(x) y(x)^b+y'(x)=0,y(x),x\right ] \]
Maple: cpu = 0.202 (sec), leaf count = 0 \[ \text {could not solve} \]
Sage: cpu = 0 (sec), leaf count = 0 \[ \text {Maxima was unable to solve this ODE} \]