[[_2nd_order, _missing_x], _Liouville, [_2nd_order, _reducible, _mu_x_y1], [_2nd_order, _reducible, _mu_xy]]
Book solution method
TO DO
Mathematica ✓
cpu = 0.08824 (sec), leaf count = 14
Maple ✓
cpu = 0.025 (sec), leaf count = 15
DSolve[(1 - 2*y[x])*y'[x]^2 + (1 + y[x]^2)*y''[x] == 0,y[x],x]
Mathematica raw output
{{y[x] -> Tan[Log[C[1]*(x + C[2])]]}}
Maple raw input
dsolve((1+y(x)^2)*diff(diff(y(x),x),x)+(1-2*y(x))*diff(y(x),x)^2 = 0, y(x),'implicit')
Maple raw output
exp(arctan(y(x)))-_C1*x-_C2 = 0