1/1x3+1/3x5+1/5x7+1/7x9+1/9x11+1/11x13=
1/1x3+1/3x5+1/5x7+1/7x9+1/9x11=?
2x2/1x3+4x4/3x5+6x6/5x7+8x8/7x9+10x10/9x11+12x12/11x13 仔细看看
2/1x3+2/3X5+2/5x7=2/7x9+2/9x11
因式分解:X15+X14+X13+X12+X11+X10+X9+X8+X7+X6+X5+X4+X3+X2+X+1
已知1-1/3=2/1x3,计算1/1x3+1/3x5+1/5x7+1/7x9+1/9x11=
计算:1/1x3+1/3x5+1/5x7+1/7x9+……+1/2011x2013
1X3分之一+3X5分之一+5X7分之一+7X9分之一加到2009X2011分之一怎么算,
1+2X3+4X5+6X7+8X9=303
计算:1/1x2+1/2x3+1/3x4+1/4x5+1/5x6+1/6x7+1/7x8+1/8x9+1/9x10.
model:Min=x1+x2+x3+x4+x5+x6+x7+x8+x9+x10+x11+x12+x13+x14+x15
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