\[ y''(x)=-\frac {2 (a+x) y'(x)}{x^2}-\frac {b y(x)}{x^4} \] ✓ Mathematica : cpu = 0.0145468 (sec), leaf count = 89
\[\left \{\left \{y(x)\to c_1 e^{-\frac {\sqrt {b} \left (-\frac {\sqrt {a^2-b}}{\sqrt {b}}-\frac {a}{\sqrt {b}}\right )}{x}}+c_2 e^{-\frac {\sqrt {b} \left (\frac {\sqrt {a^2-b}}{\sqrt {b}}-\frac {a}{\sqrt {b}}\right )}{x}}\right \}\right \}\]
✓ Maple : cpu = 0.059 (sec), leaf count = 43
\[ \left \{ y \left ( x \right ) ={\it \_C1}\,{{\rm e}^{{\frac {1}{x} \left ( a-\sqrt {{a}^{2}-b} \right ) }}}+{\it \_C2}\,{{\rm e}^{{\frac {1}{x} \left ( a+\sqrt {{a}^{2}-b} \right ) }}} \right \} \]