\[ y'(x)=\frac {2 a \left (-4 a+x y(x)^2+x\right )}{-128 a^4+96 a^3 x y(x)^2-24 a^2 x^2 y(x)^4+2 a x^3 y(x)^6+4 a x^2 y(x)-x^3 y(x)^3-x^3 y(x)} \] ✓ Mathematica : cpu = 1.301 (sec), leaf count = 401
\[\left \{\left \{y(x)\to \text {Root}\left [8 \text {$\#$1}^5 a x^2-8 \text {$\#$1}^4 a c_1 x^2-64 \text {$\#$1}^3 a^2 x+\text {$\#$1}^2 \left (2 x^2+64 a^2 c_1 x\right )+128 \text {$\#$1} a^3-128 a^3 c_1-8 a x+x^2\& ,1\right ]\right \},\left \{y(x)\to \text {Root}\left [8 \text {$\#$1}^5 a x^2-8 \text {$\#$1}^4 a c_1 x^2-64 \text {$\#$1}^3 a^2 x+\text {$\#$1}^2 \left (2 x^2+64 a^2 c_1 x\right )+128 \text {$\#$1} a^3-128 a^3 c_1-8 a x+x^2\& ,2\right ]\right \},\left \{y(x)\to \text {Root}\left [8 \text {$\#$1}^5 a x^2-8 \text {$\#$1}^4 a c_1 x^2-64 \text {$\#$1}^3 a^2 x+\text {$\#$1}^2 \left (2 x^2+64 a^2 c_1 x\right )+128 \text {$\#$1} a^3-128 a^3 c_1-8 a x+x^2\& ,3\right ]\right \},\left \{y(x)\to \text {Root}\left [8 \text {$\#$1}^5 a x^2-8 \text {$\#$1}^4 a c_1 x^2-64 \text {$\#$1}^3 a^2 x+\text {$\#$1}^2 \left (2 x^2+64 a^2 c_1 x\right )+128 \text {$\#$1} a^3-128 a^3 c_1-8 a x+x^2\& ,4\right ]\right \},\left \{y(x)\to \text {Root}\left [8 \text {$\#$1}^5 a x^2-8 \text {$\#$1}^4 a c_1 x^2-64 \text {$\#$1}^3 a^2 x+\text {$\#$1}^2 \left (2 x^2+64 a^2 c_1 x\right )+128 \text {$\#$1} a^3-128 a^3 c_1-8 a x+x^2\& ,5\right ]\right \}\right \}\] ✓ Maple : cpu = 3.685 (sec), leaf count = 71
\[\left \{c_{1}+\frac {x y \left (x \right )^{4}+\left (-4 a +x \right ) y \left (x \right )^{2}-2 a}{2 \left (-x y \left (x \right )^{2}+4 a \right )^{2} a y \left (x \right )^{4}}+\frac {8 a y \left (x \right )^{5}+2 y \left (x \right )^{2}+1}{16 a^{2} y \left (x \right )^{4}} = 0\right \}\]