\[ \boxed { {x}^{2} \left ( {\frac {\rm d}{{\rm d}x}}y \left ( x \right ) \right ) ^{2}- \left ( y \left ( x \right ) \right ) ^{4}+ \left ( y \left ( x \right ) \right ) ^{2}=0} \]
Mathematica: cpu = 0.037005 (sec), leaf count = 111 \[ \left \{\left \{y(x)\to \sqrt {\tan ^2\left (c_1-\log (x)\right )+1} \left (-\cot \left (c_1-\log (x)\right )\right )\right \},\left \{y(x)\to \sqrt {\tan ^2\left (c_1-\log (x)\right )+1} \cot \left (c_1-\log (x)\right )\right \},\left \{y(x)\to \sqrt {\tan ^2\left (c_1+\log (x)\right )+1} \left (-\cot \left (c_1+\log (x)\right )\right )\right \},\left \{y(x)\to \sqrt {\tan ^2\left (c_1+\log (x)\right )+1} \cot \left (c_1+\log (x)\right )\right \}\right \} \]
Maple: cpu = 0.561 (sec), leaf count = 62 \[ \left \{ y \left ( x \right ) =-1,y \left ( x \right ) =1,y \left ( x \right ) ={\frac {1}{\tan \left ( -\ln \left ( x \right ) +{\it \_C1} \right ) }\sqrt { \left ( \tan \left ( -\ln \left ( x \right ) +{\it \_C1 } \right ) \right ) ^{2}+1}},y \left ( x \right ) =-{\frac {1}{\tan \left ( -\ln \left ( x \right ) +{\it \_C1} \right ) }\sqrt { \left ( \tan \left ( -\ln \left ( x \right ) +{\it \_C1} \right ) \right ) ^{2}+1 }} \right \} \]