[[_high_order, _linear, _nonhomogeneous]]
Book solution method
TO DO
Mathematica ✓
cpu = 0.117397 (sec), leaf count = 46
Maple ✓
cpu = 0.151 (sec), leaf count = 41
DSolve[y[x] + 2*y''[x] + y''''[x] == 24*x*Sin[x],y[x],x]
Mathematica raw output
{{y[x] -> (3 - 3*x^2 + C[1] + x*C[2])*Cos[x] + ((-2*x^3 + 2*C[3] + x*(9 + 2*C[4]
))*Sin[x])/2}}
Maple raw input
dsolve(diff(diff(diff(diff(y(x),x),x),x),x)+2*diff(diff(y(x),x),x)+y(x) = 24*x*sin(x), y(x),'implicit')
Maple raw output
y(x) = 1/2*(2*_C3*x-6*x^2+2*_C1+3)*cos(x)-(x^3+(-_C4-3)*x-_C2)*sin(x)