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用规律计算:1/1+√2+1/√2+√3+1/√3√4+、、、+1/√2008+√2009+1/√2009√2010+1

来源:学生作业帮 编辑:神马作文网作业帮 分类:数学作业 时间:2024/10/04 04:17:54
用规律计算:1/1+√2+1/√2+√3+1/√3√4+、、、+1/√2008+√2009+1/√2009√2010+1/√2010+√2011
根据(√2-1)*(√2+1)=1
(√3-√2)*(√3+√2)=1
(√2005-√2004)*(√2005+√2004)=1
用规律计算:1/1+√2+1/√2+√3+1/√3√4+、、、+1/√2008+√2009+1/√2009√2010+1
由规律可知:
1/(1+√2) +1/(√2+√3)+1/(√3+√4)+...+1/(√2009+√2010)+1/(√2010+√2011)
=(√2 -1)/[(1+√2)(√2 -1)] +(√3-√2)/[(√2+√3)(√3-√2)]+(√4-√3)/[(√3+√4)(√4-√3)]+...
+(√2010-√2009)/[(√2009+√2010)(√2010+√2009)]
+(√2011-√2010)/[(√2010+√2011)(√2011+√2010)]
=(√2 -1)+(√3-√2)+(√4-√3)+...+(√2010-√2009)+(√2011-√2010)
=(√2011) -1