公式

果然翁。﹏。

有冇人可以解釋同俾多邊形既公式我

cyrun_ncp827

係比1隻內角你,叫你搵幾多條邊?
係比1隻外角你,叫你搵幾多條邊?
係比幾多條邊你,叫你搵一隻角幾度?
係比1幾多條邊你,叫你搵1隻外角幾角?
好多個問題,,,
唔知你講邊個

latios

多邊形外角和=360度
多邊形內角和=(邊數目-2)*180度

仲有冇第3條....

Darksky

maybe let me show you the table of polygon and their relationship between the angles and sides

Name of polygon	Number of sides	Number of triangle inside the polygon	sum  of interior  angles
Triangles	3	1	180
Quadrilatera	4	2	360
Pentagon	5	3	540
Hexagon	6	4	720
Heptagon	7	5	900
Octagon	8	6	1080
Nonagon	9	7	1620
Decagon	10	8	1800
N-gon	n	n-2	180*(n-2)

So can you notice something?
The number inside the polygon is always 2 less than the side of the polygon
and so why is the equation always 180*(n-2)?
Becuase actually we are just dividing the polygon into triangles
thenwe may know the sum of interior angle because each triangle has 180degree and the number of triangle is always 2 less than the sides ofthe polygon
so that's why the equation is
180(sum of interior angle of a triangle)*(n-2)(the number of triangles that means 2 less than the side)
Get it now?
if you don't understand
please tell me and i'll try to say it in chinese

[ 本帖最後由 Darksky 於 15/1/2007 19:23 編輯 ]

果然翁。﹏。

對角線.......

Darksky

what do you mean by 對角線??
You want the equation of 對角線?