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主要内容

收敛区间

问题

sum, start subscript, n, equals, 1, end subscript, start superscript, infinity, end superscript, start fraction, 3, left parenthesis, x, plus, 1, right parenthesis, start superscript, n, end superscript, divided by, n, dot, 4, start superscript, n, end superscript, end fraction
收敛区间是什么?
选出正确答案:
不会做了?
不会做了?