\[ y'(x)=(y(x)+\cos (x))^2+\sin (x) \] ✓ Mathematica : cpu = 0.13083 (sec), leaf count = 18
\[\left \{\left \{y(x)\to -\cos (x)+\frac {1}{-x+c_1}\right \}\right \}\] ✓ Maple : cpu = 0.068 (sec), leaf count = 16
\[\left \{y \left (x \right ) = -\cos \left (x \right )+\frac {1}{c_{1}-x}\right \}\]