求助一道数学题初二的

先看x/(xy+x+1),因为xyz=1 ,带入其中的1,可得:
x/(xy+x+1)=1/(y+1+yz)
再看z/(xz+z+1),把xz=1/y带入可得:
z/(xz+z+1)=zy/(y+1+yz)

分母相同了,合并,结果为:
x/(xy+x+1) + y/(yz+y+1) + z/(xz+z+1)
=1/(y+1+yz)+y/(yz+y+1)+zy/(y+1+yz)
=1

1

能把问题再说清楚点吗

x/(xy+x+1)+y/(yz+y+1)+z/(xz+z+1)
=x/(xy+x+xyz)+y/(yz+y+1)+z/(xz+z+xyz)
=1/(y+1+yz)+y/(yz+y+1)+1/(x+1+xy)
=1/(y+1+yz)+y/(y+1+yz)+xyz/(x+xyz+xy)
=1/(y+1+yz)+y/(y+1+yz)+yz/(1+yz+y)
=(1+y+yz)/(y+1+yz)
=1.