Finding Vertices of octagon w/ radius r, center at origin,

[kkd70]

I am able to know that an octagon with a radius r is centered at its origin. one vertex is on the x axis. I need to know what are the coordinates of its vertices V1, V2,...Vn?

 

[Deleted member 4993]

Re: Finding Vertices

I am able to know that an octagon with a radius r is centered at its origin. one vertex is on the x axis. I need to know what are the coordinates of its vertices V1, V2,...Vn?

Hint:

Start with a sketch of the octagon and take advantage of symmetry.

Please share with us your work, indicating exactly where you are stuck - so that we know where to begin to help you.

 

[pka]

This is for a regular octagon.
Let \(\displaystyle \phi = \frac{{2\pi }}{8} = \frac{\pi }{4}\).
Then your vertices are: \(\displaystyle V_k = \left( {r\cos (k\phi ),r\sin (k\phi )} \right),\;\;k = 0,1, \cdots ,7\).