\[ a x^3 \cos (x)+x y(x) y'(x)-y(x)^2=0 \] ✓ Mathematica : cpu = 0.148438 (sec), leaf count = 38
DSolve[a*x^3*Cos[x] - y[x]^2 + x*y[x]*Derivative[1][y][x] == 0,y[x],x]
\[\left \{\left \{y(x)\to -x \sqrt {-2 a \sin (x)+c_1}\right \},\left \{y(x)\to x \sqrt {-2 a \sin (x)+c_1}\right \}\right \}\] ✓ Maple : cpu = 0.032 (sec), leaf count = 30
dsolve(x*y(x)*diff(y(x),x)-y(x)^2+a*x^3*cos(x) = 0,y(x))
\[y \left (x \right ) = \sqrt {-2 a \sin \left (x \right )+c_{1}}\, x\]