利用极限存在准则证明:limn趋向于无穷,n【1/(n^2+π)+1/(n^2+2π)+...+1/(n^2+nπ)】=1

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利用极限存在准则证明:limn趋向于无穷,n【1/(n^2+π)+1/(n^2+2π)+...+1/(n^2+nπ)】=1

利用极限存在准则证明:limn趋向于无穷,n【1/(n^2+π)+1/(n^2+2π)+...+1/(n^2+nπ)】=1
利用极限存在准则证明:limn趋向于无穷,n【1/(n^2+π)+1/(n^2+2π)+...+1/(n^2+nπ)】=1

利用极限存在准则证明:limn趋向于无穷,n【1/(n^2+π)+1/(n^2+2π)+...+1/(n^2+nπ)】=1
证明:limn【1/(n^2+π)+1/(n^2+2π)+...+1/(n^2+nπ)】limn【(1/n^2+nπ)+(1/n^2+nπ)+.(1/n^2+nπ)】
=limn(n/(n^2+nπ)
=limn/n+π)
=1
所以limn【1/(n^2+π)+1/(n^2+2π)+...+1/(n^2+nπ)】=1 成立.

lim n【1/(n^2+π)+1/(n^2+2π)+...+1/(n^2+nπ)】
=lim 1/(n+π/n)+1/(n+2π/n)+...+1/(n+π)】
=lim n*1/n
=1

迫敛准则
设 u(n) =n【1/(n^2+π)+1/(n^2+2π)+ ... +1/(n^2+nπ)】
n * n /(n^2+nπ) < u(n) < n * n / (n^2+π)
lim n->∞ n^2 /(n^2+nπ) = lim n->∞ n^2 / (n^2+π) = 1
lim n->∞ u(n)=1

夹逼准则n^2/(n^2+nπ)>n【1/(n^2+π)+1/(n^2+2π)+...+1/(n^2+nπ)】>n^2/(n^2+π)
n^2/(n^2+nπ)=n^2/(n^2+π)=1(当n趋向∞)