_________ / 5*x + 1 / ------- <= 1 - x \/ 2*x + 1
sqrt((5*x + 1)/(2*x + 1)) <= 1 - x
Or(And(-1/5 <= x, x <= 0), And(x <= -1, -oo < x))
((-1/5 <= x)∧(x <= 0))∨((x <= -1)∧(-oo < x))
(-oo, -1] U [-1/5, 0]
x in Union(Interval(-oo, -1), Interval(-1/5, 0))