4 4 sin (x) - cos (x) <= 0
sin(x)^4 - cos(x)^4 <= 0
/ / pi\ /3*pi \\ Or|And|0 <= x, x <= --|, And|---- <= x, x <= pi|| \ \ 4 / \ 4 //
((0 <= x)∧(x <= pi/4))∨((x <= pi)∧(3*pi/4 <= x))
pi 3*pi [0, --] U [----, pi] 4 4
x in Union(Interval(0, pi/4), Interval(3*pi/4, pi))