1x2+2x4+3x6+4x8 ------------------------------- 2x3+4x6+6x9+

1x2+2x4+3x6+4x8 ------------------------------- 2x3+4x6+6x9+ （1x2+2x4+3x6+4x8）/（2x3+4x6+6x9+8x12) 计算：1/1x2+1/2x3+1/3x4+1/4x5+1/5x6+1/6x7+1/7x8+1/8x9+1/9x10. 2x2/1x3+4x4/3x5+6x6/5x7+8x8/7x9+10x10/9x11+12x12/11x13 仔细看看 2x3十4x6十6x9十8x12十10x15分之1x2十2x4十3x6十4x8十5x10. 1x2/1+2x3/1+3x4/1+.+2009x2010/1=? 2x4/1+4x6/1+6x8/1+.+2010x2 某同学做一道数学题：当x=-1时，求10x9+9x8+8x7+7x6+6x5+5x4+4x3+3x2+2x+1的值，由于 小明做一道数学题，“求代数式10x9+9x8+8x7+7x6+6x5+5x4+4x3+3x2+2x+1，当x=-1时的值 某同学在做一道题：求代数式10x9+9x8+8x7+7x6+6x5+5x4+4x3+3x2+2x+1当x=-1时的值．由 1x2+2x4+3x6+4x8+5x10+.+20x40 怎么算? 1x2+2x4+3x6+4x8+5x10+.+20x40 简便计算 1x1-2x2+3x3-4x4+5x5-6x6.-100x100+101x101