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问题: 帮我找出规律并计算(要过程): 1/2+1/(2*3)+1/(3*4)…1/(2009*2010)

解答:

帮我找出规律并计算(要过程): 1/2+1/(2*3)+1/(3*4)…1/(2009*2010)

因为:
1/(2*3)=1/6=(1/2)-(1/3)
1/(3*4)=1/12=(1/3)-(1/4)
……
1/[n(n+1)]=(1/n)-[1/(n+1)]
所以:
原式=(1/2)+(1/2)-(1/3)+(1/3)-(1/4)+……+(1/2008)-(1/2009)+(1/2009)-(1/2010)
=1-(1/2010)
=2009/2010