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1/(x-1)+1/(x-1)(x-2)+1/(x-2)(x-3)+1/(x-3)(x-4)+...+1/(x-99)(

来源:学生作业帮 编辑:大师作文网作业帮 分类:数学作业 时间:2024/11/18 02:13:50
1/(x-1)+1/(x-1)(x-2)+1/(x-2)(x-3)+1/(x-3)(x-4)+...+1/(x-99)(x-100)
1/(x-1)+1/(x-1)(x-2)+1/(x-2)(x-3)+1/(x-3)(x-4)+...+1/(x-99)(
1/(x-1)+1/(x-1)(x-2)+1/(x-2)(x-3)+1/(x-3)(x-4)+...+1/(x-99)(x-100)
=1/(x-1)+1/(x-2)-1/(x-1)+1/(x-3)-1/(x-2)+.+1/(x-100)-1/(x-99)
=1/(x-100)
再问: 请问怎么得到第一步?
再答: 1/(x-1)(x-2)
=[(x-1)-(x-2)]/(x-1)(x-2)
=(x-1)/(x-1)(x-2)-(x-2)/(x-1)(x-2)
=1/(x-2)-1/(x-1)
后面的同理可得