limn趋近于正无穷{1/(n+1)^2+1/(n+2)^2+……+1/(2n)^2}=
问题描述:
limn趋近于正无穷{1/(n+1)^2+1/(n+2)^2+……+1/(2n)^2}=
答
lim(n->∞){1/(n+1)^2+1/(n+2)^2+……+1/(2n)^2}
=∫(0->1) dx/(1+x^2)
=arctanx |(0->1)
=π/4