\[ \boxed { {\frac {\rm d}{{\rm d}x}}y \left ( x \right ) +y \left ( x \right ) \cos \left ( x \right ) -{{\rm e}^{-\sin \left ( x \right ) }}=0} \]
Mathematica: cpu = 0.022503 (sec), leaf count = 23 \[ \left \{\left \{y(x)\to c_1 e^{-\sin (x)}+x e^{-\sin (x)}\right \}\right \} \]
Maple: cpu = 0.0 (sec), leaf count = 19 \[ \left \{ y \left ( x \right ) ={{\rm e}^{-\sin \left ( x \right ) }}{\it \_C1}+{{\rm e}^{-\sin \left ( x \right ) }}x \right \} \]
Sage: cpu = 0.004 (sec), leaf count = 0 \[ \left [{\left (c + x\right )} e^{\left (-\sin \left (x\right )\right )}, \text {\texttt {linear}}\right ] \]