x,y,z正整数 x>y>z证明 x^2x +y^2y+z^2z>x^(y+z)*y^(x+z)*z^(x+y)x,y,z正整数 x>y>z证明 x^2x * y^2y * z^2z>x^(y+z)*y^(x+z)*z^(x+y)不是+是 *

x,y,z正整数 x>y>z证明 x^2x +y^2y+z^2z>x^(y+z)*y^(x+z)*z^(x+y)x,y,z正整数 x>y>z证明 x^2x * y^2y * z^2z>x^(y+z)*y^(x+z)*z^(x+y)不是+是 * 证明x*x*x+y*y*y=z*z*z(x.y.z为正整数)不成立. 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? 试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y) 证明 ：x/(y+z)+y/(z+x)+z/(x+y)>=3/2其中 x,y,z>0 已知X、Y、Z都是正整数,X 已知(x+y+z)^2=x^2+y^2+z^2,证明x(y+z)+y(z+x)+z(x+y)=0 证明x-(y-z)=x-y+z 化简:(x+y-z)^3n*(z-x-y)^2n*(x-z+y)^5n(n为正整数) 证明 已知xyz∈R^+, x^2x * y^2y* z^2z≥x^y+x* y^z+x * z^x+y 化简(y-x)(z-x)/(x-2y+z)(x+y-2z)+（z-y)(x-y)/(x-2z+y)(y+z-2x)+(x-z)(y-z)/(y+z-2x)(x-2y+z) 计算:(y-x)(z-x)/(x-2y+z)(x+y-2z)+(z-y)(x-y)/(x+y-2z)(y+z-2x)+(x-z)(y-z)/(y+z-2x)(x-2y+z) 不等式x+y+z更正为正整数 计算:x^2/(x-y)(x-z)+y^2/(y-x)(y-z)+z^2/(z-x)(z-y) 急 x,y,z均为正整数,x>=y,y>=z,z>=8 x+3y-z=急x,y,z均为正整数,x>=y,y>=z,z>=8x+3y-z=132,请问1.x+y+z有最小值782.x+y+z有最大值1343.洽有一组解(x,y,z)使得x+y+z有最大值4.x+3y有最小值1405.x+2y有最大值130 已知3x+2y=4+z,2x+2z=6+y,问是否存在x、y、z的正整数值,使得x+y+z 已知一个组：x^3+y^3+z^3=x+y+z x^2+y^2+z^2=xyz 求x,y,z的正整数解 若x+2y+3z=9,求正整数x,y,z.