1/1X2+1/2X3+1/3X4...+1/100X101+101X102怎么算

1x1-2x2+3x3-4x4+5x5-6x6.-100x100+101x101 1x2+2x3+3x4+4x5······100x101答案是几? 数学题目,求速度1x2十2x3+…+100x101=1x2+2x3+…+n（n十1） 1x2x3+2+3x4+…+n(n 求线性方程组 x2-x3-x4=0 x1+x2-x3+3x4=1 x1-x2+x3+5x4=-1 x1+2x2-2x3+ 1+2x4-（x2+2x3） X1+2X2-X3+X4=1 求齐次线性方程组x1+2x2+x3+x4+x5=1 2x1+4x2+3x3+x4+x5=2 -x1-2x2+x3+3x4 设线性方程组（x1+2x2-2x3+2x4=2,x2-x3-x4=1 x1+x2-x3+3x4=a） 具体写出方程组：2x1+x2-x3+x4=1;x1+2x2+x3-x4=2;x1+x2+2x3+x4=3的通解 解方程组X2+X3+X4=1 X1+X2+X3=5 X3+X4+X5=-5 X4+X5+X1=-3 X5+X1+X2=2 1/1x2+1/2x3+1/3x4+...+1/n(n+1)怎么算 1/2x4十1/4x6十…十1/100X102