[[_2nd_order, _with_linear_symmetries]]
Book solution method
TO DO
Mathematica ✓
cpu = 0.0309123 (sec), leaf count = 74
Maple ✓
cpu = 0.234 (sec), leaf count = 63
DSolve[(b^2 + c^2*x^2)*y[x] - x*y'[x] + (a^2 - x^2)*y''[x] == 0,y[x],x]
Mathematica raw output
{{y[x] -> C[1]*MathieuC[b^2 + (a^2*c^2)/2, -(a^2*c^2)/4, ArcCos[x/a]] + C[2]*Mat
hieuS[b^2 + (a^2*c^2)/2, -(a^2*c^2)/4, ArcCos[x/a]]}}
Maple raw input
dsolve((a^2-x^2)*diff(diff(y(x),x),x)-x*diff(y(x),x)+(c^2*x^2+b^2)*y(x) = 0, y(x),'implicit')
Maple raw output
y(x) = _C1*MathieuC(1/2*a^2*c^2+b^2,-1/4*a^2*c^2,arccos(x/a))+_C2*MathieuS(1/2*a
^2*c^2+b^2,-1/4*a^2*c^2,arccos(x/a))