✓ Mathematica : cpu = 0.0402572 (sec), leaf count = 45
DSolve[-1 + y[x]^2 - 2*x*y[x]*Derivative[1][y][x] + (1 + x^2)*Derivative[1][y][x]^2 == 0,y[x],x]
✓ Maple : cpu = 0.043 (sec), leaf count = 57
dsolve((x^2+1)*diff(y(x),x)^2-2*x*y(x)*diff(y(x),x)+y(x)^2-1 = 0,y(x))