计算:-1/1×2-1/2×3-1/3×4-…-1/2007×2008(/为分号)急急急~~~~~~

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计算:-1/1×2-1/2×3-1/3×4-…-1/2007×2008(/为分号)急急急~~~~~~计算:-1/1×2-1/2×3-1/3×4-…-1/2007×2008(/为分号)急急急~~~~~~

计算:-1/1×2-1/2×3-1/3×4-…-1/2007×2008(/为分号)急急急~~~~~~
计算:-1/1×2-1/2×3-1/3×4-…-1/2007×2008(/为分号)
急急急~~~~~~

计算:-1/1×2-1/2×3-1/3×4-…-1/2007×2008(/为分号)急急急~~~~~~
原式=0-(1/1*2+1/2*3...1/2007*2008)
=0-(1-1/2+1/2-1/3+...+1/2007-1/2008)
=0-(1-1/2008)
=-2007/2008
用裂项法做,中间的数可以消掉