化简计算:(1/1+√2+1/√2+√3+1/√3+√4+.+1/√2011+√2012)

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化简计算:(1/1+√2+1/√2+√3+1/√3+√4+.+1/√2011+√2012)

化简计算:(1/1+√2+1/√2+√3+1/√3+√4+.+1/√2011+√2012)
化简计算:(1/1+√2+1/√2+√3+1/√3+√4+.+1/√2011+√2012)

化简计算:(1/1+√2+1/√2+√3+1/√3+√4+.+1/√2011+√2012)
1/(1+√2)+1/(√2+√3)+1/(√3+√4)+.+1/(√2011+√2012)
=(√2-1)/(2-1)+(√2-√3)/(2-3)+(√3-√4)/(3-4)+.+(√2011-√2012)/(2011-2012)
=-1+√2-√2+√3-√3+√4-√4+.+√2011-√2011+√2012
=√2012-1

通过分母有理化,如第一项,分子分母同时乘以(√2-1),分母变成1,分子变成(√2-1),
同理,原式=(√2-1)+(√3-√2)+…+(√2012-√2011)=√2012-1

1/1*2+1/2*3+1/3*4+.......+1/2011*2012
=1-1/2+1/2-1/3+1/3-1/4+.......+1/2011-1/2012
=1-1/2012
=2011/2012