n
R
r
n=3
R=a/Ö3
r=a/(2Ö3)
n=4
R=a/Ö2
r=a/2
n=6
R=a
r=aÖ3/2
a/2sin(180/n)
a/2tg(180/n)
0
30
45
60
90
180
270
360
1/2
Ö2/2
Ö3/2
1
-1
Ö3/3
Ö3
–