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1/1x3+1/2x4+1/3x5+1/4x6+...+1/10x12

来源：学生作业帮 编辑：神马作文网作业帮 分类：数学作业 时间：2024/11/06 13:31:21
1/1x3+1/2x4+1/3x5+1/4x6+...+1/10x12
1/1x3+1/2x4+1/3x5+1/4x6+...+1/10x12
1/1×3 + 1/2×4 + 1/3×5 +...+ 1/10×12
= (1/2)×(1 - 1/3) + (1/2)×(1/2 - 1/4) + ...+ (1/2)(1/10 - 1/12)
= (1/2)×(1 - 1/3 + 1/2 - 1/4 + ...+ 1/10 - 1/12)
= (1/2)×(1 + 1/2 - 1/11 - 1/12)
= (1/2)×175/132
= 175/264
2x2/1x3+4x4/3x5+6x6/5x7+8x8/7x9+10x10/9x11+12x12/11x13 仔细看看 （1x2+2x4+3x6+4x8）/（2x3+4x6+6x9+8x12) 计算1/1X3+1/2X4+1/3X5+.+1/10X12 1x1-2x2+3x3-4x4+5x5-6x6.-100x100+101x101 因式分解:X15+X14+X13+X12+X11+X10+X9+X8+X7+X6+X5+X4+X3+X2+X+1 x8+x7+x6+x5+x4+x3+x2+x+1因式分解 1/1X2+1/2X3+1/3X4+1/4X5+1/5X6……1/2007X2008 1x2/1+2x3/1+3x4/1+4x5/1+5x6/1+6x7/1 1/1x2+1/2x3+1/3x4+1/4x5+1/5x6+......1/2008x2009 1/1x2+1/2x3+1/3x4+1/4x5+1/5x6+1/6x7 (2X2)/1X3+(4X4)/(3X5)+(6X6)/(5X7)+...+(20X20)/(19X21)==? 2x3十4x6十6x9十8x12十10x15分之1x2十2x4十3x6十4x8十5x10.