1/1x3+1/2x4+1/3x5.1/18x20=?简便算法,
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1/1x3+1/2x4+1/3x5.1/18x20=?简便算法,
1/1x3+1/2x4+1/3x5.1/18x20=?简便算法,
1/1x3+1/2x4+1/3x5.1/18x20=?简便算法,
1/n(n+2)=[1/n-1/(n+2)]/2
1/1*3+1/2*4+1/3*5+...+1/18*20
=[(1-1/3)+(1/2-1/4)+(1/3-1/5)+...+(1/18-1/20)]/2
=[1+1/2-1/19-1/20]/2
=531/760
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解一道方程组x1+x2+x3=5,x2+x3+x4=1,x3+x4+x5=-5,x4+x5+x1=-3,x5+x1+x2=2
1/1x3+1/2x4+1/3x5+
1x2+2x3+3x4+4x5+.+15x16
x1-x2+x3=1 x2-x3+x4=2 x3-x4+x5=3 x4-x5+x1=4 x5-x1+x2=5 求x1,x2,x3,x4,x5
x5-x4+x3-x2+x-1因式分解
X5-X4+X3+X2+X+1因式分解
求解线性方程组 x1-2x2+3x3-x4-x5=2 x1+x2-x3+x4-2x5=1 2x1-求解线性方程组x1-2x2+3x3-x4-x5=2x1+x2-x3+x4-2x5=12x1-x2+x3-2x5=22x1+2x2-5x3+2x4-x5=5
求非齐次线性方程组的通解x1+3x2+5x3-4x4=1x1+3x2+2x3-2x4+x5=-1x1-2x2+x3-x4-x5=3x1+2x2+x3-x4-x5=3
若x1,x2,x3,x4,x5满足方程组:x1-x2+x3=1 x2-x3+x4=2 x3-x4+x5=3 x4-x5+x1=4 x5-x1+x2=5 求x2,x3,x4的少打了个字,是求x2,x3,x4的值
x1-x2+x3=1x2-x3+x4=21若x1,x2,x3,x4,x5满足方程组 x3-x4+x5=3x4-x5+x1=4x5-x1+x2=5求x2 x3 x4的值2已知 x1+x4+x6+x7=39 x2+x4+x5+x7=49 x3+x5+x6+x7=41 x4+x7=13 x5+x7=14 x6+x7=9 x1+x2+x3+x4+x5+x6+x7=9求x7的值若x1,x2,x3,x4,x5满足方程组 x1-x
求非其次线性方程组 {x1+2x2+x3+x4+x5=1x1+2x2+x3+x4+x5=12x1+4x2+3x3+x4+x5=2-x1-2x2+x3+3x4-x5=5 2x3+4x4-2x5=6 的一般解
线性方程组 x1+x3+x4-x5=1,x2-x3-x4=-1,2x2-x5=0,x1-x3+x4=0帮我解出来
求解一个方程急 X(1次方)+X2+X3=5 X2+X3+X4=1 X3+X4+X5=-5 X4+X5+X1=-3 X5+X1+X2=2 求X的值,
解方程组X2+X3+X4=1 X1+X2+X3=5 X3+X4+X5=-5 X4+X5+X1=-3 X5+X1+X2=2 求x1x2x3x4x5
解方程组X2+X3+X4=1 X1+X2+X3=5 X3+X4+X5=-5 X4+X5+X1=-3 X5+X1+X2=2 求x1x2x3x4x5百度里的已经看过了,求别的方式,不准抄袭
写出x的各个答案就行了.x1+x2+x3=5x2+x3+x4=1x3+x4+x5=-5x4+x5+x1=-3x5+x1+x2=2
求线性方程组的全部解,并用对应导出组的基础解系表示X1+3X2+5X3-4X4=1 X1+3X2+2X3-2X4+X5=-1 X1-2X2+X3-X4-X5=3 X1-4X2+X3+X4-X5=3 X1+2X2+X3-X4+X5=-1
简算:1/1x2+1/2x3+1/3x4+1/4x5 1/1x2 + 1/2x3 + 1/3x4 + 1/4x5