x∈[0,π]x \in[0, \pi]x∈[0,π]
x∈[0,π2]∪]π2;π]\left.\left.x \in\left[0, \frac{\pi}{2}\right] \cup\right] \frac{\pi}{2} ; \pi\right]x∈[0,2π]∪]2π;π]
x∈[0,π2[∪]π2,π]x \in\left[0, \frac{\pi}{2}[\cup] \frac{\pi}{2}, \pi\right]x∈[0,2π[∪]2π,π]
[−π2,π2]\left[-\frac{\pi}{2}, \frac{\pi}{2}\right][−2π,2π]