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How do you do this?

Show that the area of a regular polygon of n sides, each of length a is given by A=1/4n(a*a)cot(pi/n).

2007-11-07 12:24:31 · 1 answers · asked by Mia 2 in Science & Mathematics Mathematics

1 answers

Draw all the line segments connecting the center to the vertices. Then you've divided it into n isocecles triangles, each of which has an apex angle of

... try to figure this out yourself for a moment ...

2 pi/n

Now drop the median to the base of each of those triangles. You'll have 2n right triangles, each of which has an angle of ...

... that's right ...

pi/n

And one of the sides of the triangle has length a/2. And you figure out the length of the other side by using trig.

And you surely know the formula for the area of a right triangle! :)

2007-11-07 19:27:59 · answer #1 · answered by Curt Monash 7 · 0 0

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