x2+x3=2x5 x2•x3=2x6 (-x3)2 =-x6 x6÷x3=x3 把原理说一下.
已知x1+x2+x3+x4+x5+x6+x7=2010,且x1+x2=x3,x2+x3=x4,x3+x4=x5,x5+x
)设X服从N(0,1),(X1,X2,X3,X4,X5,X6)为来自总体X的简单随机样本,Y=(X1+X2+X3+)^2
(x1,x2,x3,x4,x5,x6)来自正态总体N(0,1),Y=(x1+x2+x3)^2+(x4)^2+(x5)^2
求加速度的公式:a=[(x4+x5+x6)-(x1+x2+x3)]/9t^2如果只有 x1 x2 x3 x4 x5 公式
设x1~x7是自然数,且x1<x2<...<x7,x1+x2=x3,x2+x3=x4,x3+x4=x5,x4+x5=x6
1.如果1+X+X2+X3=0,求X+X2+X3+X4+X5+X6+X7+X8的值为?
一道数学题:如果1+x+x2+x3=0,求x+x2+x3+x4+x5+x6+x7+x8的值
(2X2)/1X3+(4X4)/(3X5)+(6X6)/(5X7)+...+(20X20)/(19X21)==?
设X1,X2X,X3,X4,X5,X6,X7为自然数,相加得2010,求X1+X2+X3=?
设x1,x2,x3,x4,x5,x6,x7是自然数,且x1<x2<x3<x4<x5<x6<x7,x1+x2=x3,x2+
Min Z= X1 +X2 +X3 +X4 +X5 +X6 +X7 +X8
1x1-2x2+3x3-4x4+5x5-6x6.-100x100+101x101