a^2=2 b^3=3
(a^2)^3=a^6=2^3=8
(b^3)^2=b^6=3^2=9
所以 ac
a^2=2 c^5=5
(a^2)^5=a^10=2^5=32
(c^5)^2=c^10=5^2=25
所以a>c
所以
b>a>c