(1+1X2)/ 250+(3+2X2)/250+(5+2X3)/250+.+(999+2X500)/250
求线性方程组 x2-x3-x4=0 x1+x2-x3+3x4=1 x1-x2+x3+5x4=-1 x1+2x2-2x3+
因式分解(1+x+x2+x3)2-x3
求解运筹学试题,急,已知线性规划问题:maxZ=2x1+3x2-5x3 x1+x2+x3=7 2x1-5x2+x3>=1
解方程组X2+X3+X4=1 X1+X2+X3=5 X3+X4+X5=-5 X4+X5+X1=-3 X5+X1+X2=2
证明:(x3+5x2+4x-1)-(-x2-3x+2x3-3)+(8-7x-6x2+x3)的值与x无关.
已知x2+3x2+1=0,求x3+x3分之一+2的值
分解因式:-27x3+8 ,(x2-5x+2)(x2-5x+4)-24 ,x5+x4+x3+x2+x1+1
x2+x=1求x3+2x2-7
解方程组X1+X2+X3=0,2X2-X3=1,X1-X2+2X3=-1.
已知X1+x2+X2+...+Xn=1,证明不等式:X1^2/(X1+X2)+X2^2/(X2+X3)+X3^2/(X3
1+2x4-(x2+2x3)
X1+2X2-X3+X4=1