计算1/(1+√2)+1/(√2+√3)+.+1/(√2010+√2011)√是根号

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计算1/(1+√2)+1/(√2+√3)+.+1/(√2010+√2011)√是根号
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计算1/(1+√2)+1/(√2+√3)+.+1/(√2010+√2011)√是根号
计算1/(1+√2)+1/(√2+√3)+.+1/(√2010+√2011)
√是根号

计算1/(1+√2)+1/(√2+√3)+.+1/(√2010+√2011)√是根号
=1(1-√2)/(1+√2)(1-√2)+1(√2-√3)/(√2+√3)(√2-√3)+.+1(√2010-√2011)/(√2010+√2011)(√2010-√2011)
=1(1-√2)/(-1)+1(√2-√3)/(-1)+.+1(√2010-√2011)/(-1)
=(-1+√2)+(-√2+√3)+.+(-√2010+√2011)
=-1+√2011
你可以列在草稿纸上看下

1/(√n+√n+1)= (√n-√n+1)/(√n+√n+1)(√n-√n+1)=√n-√n+1
原式=(√2-1)+(√3-√2)+...+(√2011-√2010)=√2011-1

1/(1+√2)+1/(√2+√3)+......+1/(√2010+√2011)
分子分母同时乘以有理化因式
=√2-1+√3-√2+√4-√3+............+√2011-√2010
=√2011-1

第一项乘以√2-1,第二项乘以√3-√2,照此类推,到最后一项乘以√2011-√2010,结果是√2011-1.

=(1-√2)/(1-2)+(√2-√3)/(2-3)+......+(√2010-√2011)/(2010-2011)
=√2-1+√3-√2+......+√2011-√2010
=√2011-1

分母有理化:分母都是变成1了。分子就变成:,(√2-1) +,(√3-,√2)+,(√4-,√3)+.....+,
(√2011-,√2010)中间的都相互抵消,就剩下,√2011-1

各式分别做分母有理化,得
原式= (√2-1)+(√3-√2)+...+(√2011-√2010)
=√2011-1

=(1-√2)*1/(1-√2)*(1+√2)+(√2-√3)*1/(√2-√3)*(√2+√3)+......+(√2010-√2011)*1/(√2010-√2011)*(√2010+√2011)
分母相乘后得负一
所以原式等于
=-1+√2-√2+√3+.....-√2010+√2011
=-1+√2011