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1又1/3-7/12+9/20-11/30+13/42-15/56+17/72

来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/07/04 12:39:26
1又1/3-7/12+9/20-11/30+13/42-15/56+17/72
1又1/3-7/12+9/20-11/30+13/42-15/56+17/72
=1/3-(3+4)/(3*4)+(4+5)/(4*5)-(5+6)/(5*6)+(6+7)/42-(7+8)/(7*8)+(8+9)/(8*9)
=1/3-1/3-1/4+1/4+1/5-1/5-1/6+1/6+1/7-1/7-1/8+1/8+1/9
=10/9 再答: =1又1/3-(3+4)/(3*4)+(4+5)/(4*5)-(5+6)/(5*6)+(6+7)/42-(7+8)/(7*8)+(8+9)/(8*9)
=1又1/3-1/3-1/4+1/4+1/5-1/5-1/6+1/6+1/7-1/7-1/8+1/8+1/9
=10/9