x/2=/y3=z/4 x+y+z=18紧急!

x/2=/y3=z/4 x+y+z=18紧急! x+y+z=0求 x3+y3+z3=? 因式分解：x3(y-z)+y3(z-x)+z3(x-y)= 已知x,y,z是正实数,且x-y=-2,y3-z3-y2-yz-z=0,求x-z的值 x-4y+z=-302x+y-z=18x--y-z=7 x+y/2=z+x/3=y+z/4 x+y+z=27 x+2y=3x+2z=4y+z 求x:y:z 若x,y,z成等差数列,则(z-x)^2-4(x-y)(y-z)= (x*x+2)(y*y+4)(z*z+8)=64xyz,求x,y,z 已知x+y+z=2,x2+y2+z2=12则x3+y3+z3= 已知x+y+z=2,x2+y2+z2=12则x3+y3+z3= 为什么（y3/z+z3/x+x3/y）(yz+zx+xy)>=(y2+x2+z2)2 1.X+Y+Z=6X+2Y+3Z=12182.X+Y=2572X×2=96Y3.X+Y=682X+4Y=208 (x+y-z)(x-y+z)= 2x+z=10 x+y-z=4 3x-y-z=0 用行列式的性质证明：y+z z+x x+y x y z x+y y+z z+x =2 z x y z+x x+y y+z y z x 这个怎么证? (x-2y+z)(x+y-2z)分之（y-x)(z-x) + (x+y-2z)(y+z-2x)分之(z-y)(x-y) + (y+z-2z)(x-2y+z)分之（x-z)(y-z)=?第三部分那个是 （y+z-2x)(x-2y+z)分之（x-z)(y-z) 如果x/2=y/3=z/4,且x+y+z=18,那么x+y-z=?