log(3,2)=lg2/lg3 ln2=lg2/lge 而e=2.718....<3 所以lg3>lge>lg2>0 所以ln2>log(3,2)所以ln2>log(3,2)>log(4,2)=1/2=4^(-1/2)>5^(-1/2)
分别设三个数为a,b,c由换底公式可得a=log3(2)=1/log2(3)b=ln2=log e(2)=log2.7(2)=1/log2(2.7)所以alog3(2)=lg2/lg3>lg2/lg4=1/2而5^(-1/2)=1/5^(1/2)<1/4^(1/2)=1/2所以c