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用数学归纳法证明对所有整数 n >= 0 , integrate from 0 to infinity of x^n e^(-x) dx = n! ,在归纳步骤中使用分部积分。
用数学归纳法证明对所有整数 n >= 0 , integrate from 0 to infinity of x^n e^(-x) dx = n! ,在归纳步骤中使用分部积分。
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