2²/1×3+4²/3×5+6²/5×7+8²/7×9+……+2010²/2009×2011

2²/1×3+4²/3×5+6²/5×7+8²/7×9+……+2010²/2009×2011
2²/1×3+4²/3×5+6²/5×7+8²/7×9+……+2010²/2009×2011

2²/1×3+4²/3×5+6²/5×7+8²/7×9+……+2010²/2009×2011
2²/1×3+4²/3×5+6²/5×7+8²/7×9+……+2010²/2009×2011
=1+1/1*3+1+1/3*5+1+1/5*7+.+1+1/2009*2011
=1005+(1-1/3+1/3-1/5+1/5-1/7+.+1/2009-1/2011)
=1005+1-1/2011
=1005+2010/2011
=1005又2010/2011

2²/1×3+4²/3×5+6²/5×7+8²/7×9+……+2010²/2009×2011
=1+1/1*3+1+1/3*5+1+1/5*7+............+1+1/2009*2011
=1005+(1-1/3+1/3-1/5+1/5-1/7+.......+1/2009-1/2011)
=1005+1-1/20...

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2²/1×3+4²/3×5+6²/5×7+8²/7×9+……+2010²/2009×2011
=1+1/1*3+1+1/3*5+1+1/5*7+............+1+1/2009*2011
=1005+(1-1/3+1/3-1/5+1/5-1/7+.......+1/2009-1/2011)
=1005+1-1/2011
=1005+2010/2011
=1005又2010/2011 不会的题目应该要多问老师，要做到不耻下问，这样的·话我相信你肯定可以成功

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