\[ y''(x)=-\frac {a^2 y(x)}{x^4}-\frac {2 y'(x)}{x} \] ✓ Mathematica : cpu = 0.0110433 (sec), leaf count = 25
\[\left \{\left \{y(x)\to c_1 \cos \left (\frac {a}{x}\right )-c_2 \sin \left (\frac {a}{x}\right )\right \}\right \}\]
✓ Maple : cpu = 0.012 (sec), leaf count = 21
\[ \left \{ y \left ( x \right ) ={\it \_C1}\,\sin \left ( {\frac {a}{x}} \right ) +{\it \_C2}\,\cos \left ( {\frac {a}{x}} \right ) \right \} \]