[[_3rd_order, _with_linear_symmetries]]
Book solution method
TO DO
Mathematica ✗
cpu = 135.011 (sec), leaf count = 0 , DifferentialRoot result
Maple ✓
cpu = 0.437 (sec), leaf count = 437
DSolve[(a - x)^3*(b - x)^3*y'''[x] == c*y[x],y[x],x]
Mathematica raw output
{{y[x] -> DifferentialRoot[Function[{\[FormalY], \[FormalX]}, {-(c*\[FormalY][\[
FormalX]]) + (-\[FormalX] + a)^3*(-\[FormalX] + b)^3*Derivative[3][\[FormalY]][\
[FormalX]] == 0, \[FormalY][0] == C[1], Derivative[1][\[FormalY]][0] == C[2], De
rivative[2][\[FormalY]][0] == C[3]}]][x]}}
Maple raw input
dsolve((a-x)^3*(b-x)^3*diff(diff(diff(y(x),x),x),x) = c*y(x), y(x),'implicit')
Maple raw output
y(x) = (x-b)^(2/(a-b)*a)*(x-a)^(-2/(a-b)*b)*((b-x)^(-1/(a-b)*RootOf(_Z^3+(-3*a-3
*b)*_Z^2+(2*a^2+8*a*b+2*b^2)*_Z-4*a^2*b-4*a*b^2-c,index = 3))*(a-x)^(1/(a-b)*Roo
tOf(_Z^3+(-3*a-3*b)*_Z^2+(2*a^2+8*a*b+2*b^2)*_Z-4*a^2*b-4*a*b^2-c,index = 3))*_C
3+(b-x)^(-1/(a-b)*RootOf(_Z^3+(-3*a-3*b)*_Z^2+(2*a^2+8*a*b+2*b^2)*_Z-4*a^2*b-4*a
*b^2-c,index = 2))*(a-x)^(1/(a-b)*RootOf(_Z^3+(-3*a-3*b)*_Z^2+(2*a^2+8*a*b+2*b^2
)*_Z-4*a^2*b-4*a*b^2-c,index = 2))*_C2+(b-x)^(-1/(a-b)*RootOf(_Z^3+(-3*a-3*b)*_Z
^2+(2*a^2+8*a*b+2*b^2)*_Z-4*a^2*b-4*a*b^2-c,index = 1))*(a-x)^(1/(a-b)*RootOf(_Z
^3+(-3*a-3*b)*_Z^2+(2*a^2+8*a*b+2*b^2)*_Z-4*a^2*b-4*a*b^2-c,index = 1))*_C1)