设log2x=log3y=log5z=t tx=2^t,y=3^t,z=5^t a=2^(t/2),b=3^(t/3),z=5^(t/5) a/b=[(2^(1/2)/(3^(1/3)]^t =[根号2/三次根号3]^t (根号2/三次根号3)^6=2^3/3^2=8/9根号2/三次根号31==>a>b 同理可以判断:aa>b...