\[ y'(x)=-\frac {e^x \left (-8 y(x)^{9/2}+36 e^x y(x)^3-8 y(x)^3+24 e^x y(x)^{3/2}-54 e^{2 x} y(x)^{3/2}-18 e^{2 x}+27 e^{3 x}-8\right )}{8 \sqrt {y(x)}} \] ✓ Mathematica : cpu = 1.50614 (sec), leaf count = 68
DSolve[Derivative[1][y][x] == -1/8*(E^x*(-8 - 18*E^(2*x) + 27*E^(3*x) + 24*E^x*y[x]^(3/2) - 54*E^(2*x)*y[x]^(3/2) - 8*y[x]^3 + 36*E^x*y[x]^3 - 8*y[x]^(9/2)))/Sqrt[y[x]],y[x],x]
\[\text {Solve}\left [\frac {2}{3} \log \left (y(x)^{3/2}-\frac {3 e^x}{2}\right )+e^x=\frac {4}{9 e^x-6 y(x)^{3/2}}+\frac {2}{3} \log \left (y(x)^{3/2}-\frac {3 e^x}{2}+1\right )+c_1,y(x)\right ]\] ✓ Maple : cpu = 0.864 (sec), leaf count = 49
dsolve(diff(y(x),x) = -1/8*(-8-8*y(x)^3+24*y(x)^(3/2)*exp(x)-18*exp(x)^2-8*y(x)^(9/2)+36*y(x)^3*exp(x)-54*y(x)^(3/2)*exp(x)^2+27*exp(x)^3)*exp(x)/y(x)^(1/2),y(x))
\[{\mathrm e}^{x}-\frac {4}{-6 y \left (x \right )^{\frac {3}{2}}+9 \,{\mathrm e}^{x}}+\frac {2 \ln \left (y \left (x \right )^{\frac {3}{2}}-\frac {3 \,{\mathrm e}^{x}}{2}\right )}{3}-\frac {2 \ln \left (y \left (x \right )^{\frac {3}{2}}-\frac {3 \,{\mathrm e}^{x}}{2}+1\right )}{3}-c_{1} = 0\]