[_separable]
Book solution method
Separable ODE, Neither variable missing
Mathematica ✓
cpu = 0.0374284 (sec), leaf count = 63
Maple ✓
cpu = 0.013 (sec), leaf count = 17
DSolve[Sqrt[1 + x^2]*(1 + y[x])*y'[x] == y[x]^3,y[x],x]
Mathematica raw output
{{y[x] -> -(1 + Sqrt[1 - 2*ArcSinh[x] - 2*C[1]])/(2*(ArcSinh[x] + C[1]))}, {y[x]
-> (-1 + Sqrt[1 - 2*ArcSinh[x] - 2*C[1]])/(2*(ArcSinh[x] + C[1]))}}
Maple raw input
dsolve((1+y(x))*diff(y(x),x)*(x^2+1)^(1/2) = y(x)^3, y(x),'implicit')
Maple raw output
arcsinh(x)+1/y(x)+1/2/y(x)^2+_C1 = 0