3x1.8×2.4=9.72

3x1/4十4x1/5十5X1/6十6X1/7十7X1/8十8X1/9十9x1/10=3x1/4十4x1/5十5X1/6十6X1/7十7X1/8十8X1/9十9x1/10=3x1/4十4x1/5十5X

1X1/2+2X1/3+3X1/4+4X1/5+……8X1/9+9X1/10=简算能让我明白原因的追加!1X1/2+2X1/3+3X1/4+4X1/5+……8X1/9+9X1/10=简算能让我明白原因

1/2x1/3+1/3x1/4+.1/8x1/9=1/2x1/3+1/3x1/4+.1/8x1/9=1/2x1/3+1/3x1/4+.1/8x1/9=1/2x1/3+1/3x1/4+.1/8x1/9=

1/2X1/3+1/3X1/4+~+1/8x1/9=?1/2X1/3+1/3X1/4+~+1/8x1/9=?1/2X1/3+1/3X1/4+~+1/8x1/9=?可以由公式得：分数的分母若是连续的两个

如果1/2*3=1/2x1/3x1/4,1/7/*4=1/7x1/8x1/9x1/10那么(1/2*4)+(1/3*3)=?如果1/2*3=1/2x1/3x1/4,1/7/*4=1/7x1/8x1/9

消元法解线性代数4X1+2X2-X3=23X1-X2+2X3=1011X1+3X2=8消元法解线性代数4X1+2X2-X3=23X1-X2+2X3=1011X1+3X2=8消元法解线性代数4X1+2X

已知x1,x2是方程x·x+3x+1=0的两个实数根·则x1·x1·x1+8x2+20=?已知x1,x2是方程x·x+3x+1=0的两个实数根·则x1·x1·x1+8x2+20=?已知x1,x2是方程

min=2*x1+3*x2;x1+x2>=350;x1>=100;2*x1+x2min=2*x1+3*x2;x1+x2>=350;x1>=100;2*x1+x2min=2*x1+3*x2;x1+x2>

1x1/2+1/2x1/3+1/3x1/4+.+1/19x1/20=?1x1/2+1/2x1/3+1/3x1/4+.+1/19x1/20=?1x1/2+1/2x1/3+1/3x1/4+.+1/19x1

1x1/2+2x1/3+3x1/4+……+8x1/9+9x1/10简便方法计算1x1/2+2x1/3+3x1/4+……+8x1/9+9x1/10简便方法计算1x1/2+2x1/3+3x1/4+……+8

奥数1/2x1/3x1/4+1/3x1/4x1/5+……+1/8x1/9x1/10奥数1/2x1/3x1/4+1/3x1/4x1/5+……+1/8x1/9x1/10奥数1/2x1/3x1/4+1/3x

maxZ=5x1+8x2x1+x2≤6?5x1+9x2≤45x1,x2≥0x1,x2取整数maxZ=5x1+8x2x1+x2≤6?5x1+9x2≤45x1,x2≥0x1,x2取整数maxZ=5x1+8

(-1X1/2)+(-1/2X1/3)+(-1/3X1/4)+……(-1/2012X1/2013)=这道题的解题方法,星期一就要期中了这货就要疯了SO……(-1X1/2)+(-1/2X1/3)+(-1

（-1x1/2）+(-1/2x1/3)+(-1/3x1/4)+.+(-1/99x1/100)=?（-1x1/2）+(-1/2x1/3)+(-1/3x1/4)+.+(-1/99x1/100)=?（-1x

1x1/2+2x1/3+3x1/4+.+99x1/100=?有谁知道这道题如何解吗1x1/2+2x1/3+3x1/4+.+99x1/100=?有谁知道这道题如何解吗1x1/2+2x1/3+3x1/4+

1/2x1/3+1/3x1/4+1/4x1/5……+1/99x1/100=?1/2x1/3+1/3x1/4+1/4x1/5……+1/99x1/100=?1/2x1/3+1/3x1/4+1/4x1/5…

F(X)=x1*x1+x1*x2+x2*x2-6*x1-3*x2求极值哪个人会做帮帮忙,F(X)=x1*x1+x1*x2+x2*x2-6*x1-3*x2求极值哪个人会做帮帮忙,F(X)=x1*x1+x

1.01x1.01x1.01x1.01x1.01x1.01x1.01x1.01x1.01x1.01=?有没有简算的?1.01x1.01x1.01x1.01x1.01x1.01x1.01x1.01x1.

X1+X2-3X3-X4=13X1-X2-3X3+4X4=4X1+5X2-9X3-8X4=0解线性方程组X1+X2-3X3-X4=13X1-X2-3X3+4X4=4X1+5X2-9X3-8X4=0解线

x1+2x2+3x3=–72x1-x2+3x3=-8-3x1-6x2-9x3=21求线性方程组x1+2x2+3x3=–72x1-x2+3x3=-8-3x1-6x2-9x3=21求线性方程组x1+2x2