a\in\langle-1,1\rangle \wedge b\in(-\frac{\pi}{2},\frac{\pi}{2})

b\in\langle-1,1\rangle \wedge a\in\langle 0,\pi\rangle

b\in\langle-1,1\rangle \wedge a\in(-\frac{\pi}{2},\frac{\pi}{2})

b\in\langle-1,1\rangle \wedge a\in\langle-\frac{\pi}{2},\frac{\pi}{2}\rangle

a\in\langle-1,1\rangle \wedge b\in\langle-\frac{\pi}{2},\frac{\pi}{2}\rangle

a\in\mathbb{R} \wedge b\in(-\frac{\pi}{2},\frac{\pi}{2})

b\in\mathbb{R} \wedge  a\in(0,\pi)

b\in\mathbb{R} \wedge a\in(-\frac{\pi}{2},\frac{\pi}{2})

a\in\langle-1,1\rangle \wedge b\in\langle 0,\pi\rangle

a\in\mathbb{R} \wedge b\in(0,\pi)