x,y,z是素数,x^y+1=z,求xyz=?我知道x=2,那么怎么确定y,z呢?我凑出来的是y=5,z=33,xyz=330hoho,对哦,33不是素数.

已知 x/(y+z)+y/(z+x)+z/(x+y)=1求 (x*x)/(y+z)+(y*y)/(x+z)+(z*z)/(x+y)=? 若xy-z=0,且(y+x)/x=(z+x)/y=(y+x)/z,求[(y+z)(z+x)(x+y)]/xyz的值? 若xy-z不等于0,且(y+x)/x=(z+x)/y=(y+x)/z,求[(y+z)(z+x)(x+y)]/xyz的值? 若|x-3|+|y+2|+|2z+1|=0,求(xy-yz)(y-x+z) 设z=z(x,y)是由方程e^(-xy)+2z-e^z=2确定 求dz|(x=2,y=-1/2) 设z=z(x,y)是由方程e^(-xy)+2z-e^z=2确定 求dz|(x=2,y=-1/2) 已知x+y+yz=5,y+z+xy=8,x+z+xy=9,求x,y,z 若xyz=1,求 x/(xy+x+1) +y/(yz+y+z) +z/(zx+z+1)越快越好~. 已知XY+X/X+Y+1=2 XZ+2X/X+Z+2=3 (Y+1)(Z+2)/Y+Z+3=4 求X+Y+Z的值已知(XY+X)/(X+Y+1)=2 (XZ+2X)/(X+Z+2)=3 [(Y+1)(Z+2)]/(Y+Z+3)=4 求X+Y+Z的值 z=f(x+y,xy,x/y),求z对于xy的二次导数 求z=xy+1／x+1／y的极值 设x,y,z是实数,且(x-y)^2+(y-z)^2+(z-x)^2=(x+y-2z)^2+(y+z-2x)^2+(z+x-2y)^2求[(xy+1)(yz+1)(zx+1)]/[(x^2+1)(y^2+1)(z^2+x)]的值. X*(Y+Z)=209,X、Y、Z是质数,求X、Y、Z. X*(Y+Z)=209,X,Y,Z是质数,求X,Y,Z. 求函数Z=x^xy的偏导数答案是Z=f'x(x,y)=yx^xy(lnx+1),Z=f'y(x,y)=x^(xy+1)lnx, 已知XY=2(X+Y),YZ=4(Y+Z),ZX=5(Z+X),求X,Y,Z已知XY=2(X+Y),YZ=4(Y+Z),ZX=5(Z+X),求X,Y,Z 若x-y=6,xy=-8,求代数式(x+y+z)²+(x-y-z)(x-y+z)-2·z(x+y)的值 若x+y=6,xy=-8,求代数式(x+y-z)^2+(x+y-z)(x+y+z)-2·z(x-y)