设数列un收敛于S,则级数un+1-un收敛于
问题描述：
设数列un收敛于S,则级数un+1-un收敛于
答
lim(n->无穷)un = S = lim(n->无穷)u(n+1)
lim(n->无穷)(u(n+1) - un ) = 0