Trigonometria do círculo

	0	$\pi\over 6$	$\pi\over 4$	$\pi\over 3$	$\pi\over 2$
$\sin x$	0	1/2	$\sqrt {2}/2$	$\sqrt {3}/2$	1
$\cos x$	1	$\sqrt {3}/2$	$\sqrt {2}/2$	1/2	0
$\tan x$	0	$\sqrt{3}/3$	1	$\sqrt {3}$	$\infty$
$\cot x$	$\infty$	$\sqrt {3}$	1	$\sqrt{3}/3$	0

truemm