ODE
\[ y'''(x)+3 y''(x)-y'(x)-3 y(x)=0 \] ODE Classification
[[_3rd_order, _missing_x]]
Book solution method
TO DO
Mathematica ✓
cpu = 0.010134 (sec), leaf count = 28
\[\left \{\left \{y(x)\to c_1 e^{-3 x}+c_2 e^{-x}+c_3 e^x\right \}\right \}\]
Maple ✓
cpu = 0.01 (sec), leaf count = 21
\[ \left \{ y \left ( x \right ) ={\it \_C1}\,{{\rm e}^{-3\,x}}+{{\rm e}^{x}}{\it \_C2}+{\it \_C3}\,{{\rm e}^{-x}} \right \} \] Mathematica raw input
DSolve[-3*y[x] - y'[x] + 3*y''[x] + y'''[x] == 0,y[x],x]
Mathematica raw output
{{y[x] -> C[1]/E^(3*x) + C[2]/E^x + E^x*C[3]}}
Maple raw input
dsolve(diff(diff(diff(y(x),x),x),x)+3*diff(diff(y(x),x),x)-diff(y(x),x)-3*y(x) = 0, y(x),'implicit')
Maple raw output
y(x) = _C1*exp(-3*x)+exp(x)*_C2+_C3*exp(-x)