4 2 x - 13*x + 36 >= 0
x^4 - 13*x^2 + 36 >= 0
Or(And(-2 <= x, x <= 2), And(3 <= x, x < oo), And(x <= -3, -oo < x))
((-2 <= x)∧(x <= 2))∨((3 <= x)∧(x < oo))∨((x <= -3)∧(-oo < x))
(-oo, -3] U [-2, 2] U [3, oo)
x in Union(Interval(-oo, -3), Interval(-2, 2), Interval(3, oo))