数学题 急！~~~~~~~~~~~~~~~

x+y+z=0,
a^(yz)=b^(xz)=c^(xy)，

(a^y)^z=(b^x)z......a^y=b^x

(a^z)^y=(c^x)y......a^z=c^x

(b^z)^x=(c^y)x......b^z=c^y

a^y*a^z*b^z=b^x*c^x*c^y

a^(y+z)*b^z=b^x*c^(x+y)
a^(-x)*b^z=b^x*c^(-z)
(cb)^z=(ab)^x
a^z*(cb)^z=a^z*(ab)^x

(abc)^z=a^(z+x)*b^x=a^(-y)*b^x=a^y/b^x=1

如果z≠0,那只有abc=1.

答案是1. 理由:取x=1,y=1,z=-2即可推算最简单!