\[ \left (x^2+1\right ) y''(x)+x y'(x)-9 y(x)=0 \] ✓ Mathematica : cpu = 0.0132501 (sec), leaf count = 25
\[\left \{\left \{y(x)\to i c_2 \sinh \left (3 \sinh ^{-1}(x)\right )+c_1 \cosh \left (3 \sinh ^{-1}(x)\right )\right \}\right \}\] ✓ Maple : cpu = 0.018 (sec), leaf count = 19
\[y \relax (x ) = c_{1} \sinh \left (3 \arcsinh \relax (x )\right )+c_{2} \cosh \left (3 \arcsinh \relax (x )\right )\]