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