A = log 1 / 3 log 2 / 2 log B = log 1 / 2 log 3 log 4 / 3 log Then the size relation of a, B and C is

A = log 1 / 3 log 2 / 2 log B = log 1 / 2 log 3 log 4 / 3 log Then the size relation of a, B and C is

From the known a = log3 (2), C = log3 (4 / 3), we can get a > C, obviously easy to get b > C
5*a=5*log3(2)>log3(27)=3
5*b=5*log1/2(2/3)=5*log2(3/2)0.6,bb>c