let $$P_n$$ be the perimeter of n-sided gon inscribed in the circle with radius r
a) show that $$\lim_{n\to \infty}P_n=2nr\sin(\frac{\pi}{n})$$

Question

let $$P_n$$ be the perimeter of n-sided gon inscribed in the circle with radius r
a) show that $$\lim_{n\to \infty}P_n=2nr\sin(\frac{\pi}{n})$$

xapproachesinfinity · Answer

any ideas here.
what i thought of is see the perimeter in term of sides "s"
so the perimeter is $$P_n=ns$$
I'm looking for how to write s in otherway

perl · Answer

i am going to use the case n=8 to develop a general formula

perl · Answer

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xapproachesinfinity · Answer

oh i see, well i started do some similar things
let me see where you take it

perl · Answer

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rational · Answer

that limit has some problem, n should not present on right hand side

perl · Answer

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