高数积分题,具体过程!

问题描述:

高数积分题,具体过程!
n
lim sin(π/n) ∑ [1/(1 + Cos[k/n])]
n->无穷大k=1
n在∑上面,k=1在∑下面

=sin(π/n)/ (π/n)lim π/n ∑ [1/(1 + Cos[k/n])]
=lim π/n ∑ [1/(1 + Cos[k/n])]
=πlim 1/n ∑ [1/(1 + Cos[k/n])]
=π积分号[1/(1 + Cosx)]dx(x从0到1)
下面的过程就不详述了.