\[ \frac {1}{2} (a-b) y(x)+x^a y(x)^2+x^b+x y'(x)=0 \] ✓ Mathematica : cpu = 0.213631 (sec), leaf count = 40
DSolve[x^b + ((a - b)*y[x])/2 + x^a*y[x]^2 + x*Derivative[1][y][x] == 0,y[x],x]
\[\left \{\left \{y(x)\to -x^{\frac {b-a}{2}} \tan \left (\frac {2 x^{\frac {a+b}{2}}}{a+b}-c_1\right )\right \}\right \}\] ✓ Maple : cpu = 0.062 (sec), leaf count = 41
dsolve(x*diff(y(x),x)+x^a*y(x)^2+1/2*(a-b)*y(x)+x^b = 0,y(x))
\[y \left (x \right ) = -\tan \left (\frac {2 x^{\frac {a}{2}+\frac {b}{2}}+c_{1} \left (a +b \right )}{a +b}\right ) x^{-\frac {a}{2}+\frac {b}{2}}\]