你好,很高兴为你解答|1/3-1/2|+|1/4-1/3|+|1/5-1/4|+···+|1/2009-1/2008|=1/2-1/3+1/3-1/4+1/4-1/5+…+1/2008-1/2009=1/2-1/2009=2007/4018
原式=1/2-1/3+1/3-1/4+1/4-1/5+……1/2008-1/2009 =1/2-1/2009 =(2009-2)/4018 =2007/4018
去绝对值,直接相消就行
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