ODE
\[ y'''(x)+3 y''(x)+3 y'(x)+y(x)=0 \] ODE Classification
[[_3rd_order, _missing_x]]
Book solution method
TO DO
Mathematica ✓
cpu = 0.15113 (sec), leaf count = 23
\[\left \{\left \{y(x)\to e^{-x} (x (c_3 x+c_2)+c_1)\right \}\right \}\]
Maple ✓
cpu = 0.01 (sec), leaf count = 27
\[[y \left (x \right ) = {\mathrm e}^{-x} \textit {\_C1} +\textit {\_C2} \,{\mathrm e}^{-x} x +\textit {\_C3} \,{\mathrm e}^{-x} x^{2}]\] Mathematica raw input
DSolve[y[x] + 3*y'[x] + 3*y''[x] + y'''[x] == 0,y[x],x]
Mathematica raw output
{{y[x] -> (C[1] + x*(C[2] + x*C[3]))/E^x}}
Maple raw input
dsolve(diff(diff(diff(y(x),x),x),x)+3*diff(diff(y(x),x),x)+3*diff(y(x),x)+y(x) = 0, y(x))
Maple raw output
[y(x) = exp(-x)*_C1+_C2*exp(-x)*x+_C3*exp(-x)*x^2]