[[_high_order, _missing_x]]
Book solution method
TO DO
Mathematica ✓
cpu = 0.00952887 (sec), leaf count = 50
Maple ✓
cpu = 0.005 (sec), leaf count = 37
DSolve[6*y[x] + 5*y''[x] + y''''[x] == 0,y[x],x]
Mathematica raw output
{{y[x] -> C[3]*Cos[Sqrt[2]*x] + C[1]*Cos[Sqrt[3]*x] + C[4]*Sin[Sqrt[2]*x] + C[2]
*Sin[Sqrt[3]*x]}}
Maple raw input
dsolve(diff(diff(diff(diff(y(x),x),x),x),x)+5*diff(diff(y(x),x),x)+6*y(x) = 0, y(x),'implicit')
Maple raw output
y(x) = _C1*sin(3^(1/2)*x)+_C2*cos(3^(1/2)*x)+_C3*sin(2^(1/2)*x)+_C4*cos(2^(1/2)*
x)