Question

賴鉅元

請問40題怎麼證，不太會

WOW 了at a regular polygon of 7 sides inscribed ina
ecle ofTadius 7has perimeter zz 三 2 sin (元/7)

全 生

ad ge a Te OKTINo to 說 5

CM

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Answer 1

annoyance

lim[(n^2+n)^(1/2)-n]
=lim[n(1+1/n)^(1/2)-1]
=lim n[(1+1/n)^(1//2)-1][(1+1/n)^(1/2)+1]/(1+1/n)^(1/2)+1
=lim 1/[(1+1/n)^(1/2)+1], n->infinite,1/n = 0
=>lim 1/[(1+1/n)^(1/2)+1]=1/2