\[ \boxed { {\frac {\rm d}{{\rm d}x}}y \left ( x \right ) ={\frac { \left ( y \left ( x \right ) -\ln \left ( x \right ) -{\it Ci} \left ( x \right ) \right ) ^{2}+\cos \left ( x \right ) }{x}}=0} \]
Mathematica: cpu = 0.472560 (sec), leaf count = 27 \[ \left \{\left \{y(x)\to \frac {x^2}{c_1-\frac {x^2}{2}}+\text {Ci}(x)+\log (x)+1\right \}\right \} \]
Maple: cpu = 0.281 (sec), leaf count = 27 \[ \left \{ y \left ( x \right ) =\ln \left ( x \right ) +{\it Ci} \left ( x \right ) +{\frac {-{\it \_C1}\,{x}^{2}+1}{{\it \_C1}\,{x}^{2}+1}} \right \} \]