两边同时取对数得xln(1/2) = (1/3)lnx ==> -xln2 = lnx/3
==>3ln2 = -lnx/x = (1/x)ln(1/x)
令y = 1/x则ylny = 3ln2,当y>1时显然ylny随着y的增大而增大,为单调递增函数,当y=2时,ylny = 2ln2 < 3ln2,当y=3时,ylny = 3ln3 >3ln2,结合单调性可知2
两边同时取对数得xln(1/2) = (1/3)lnx ==> -xln2 = lnx/3
==>3ln2 = -lnx/x = (1/x)ln(1/x)
令y = 1/x则ylny = 3ln2,当y>1时显然ylny随着y的增大而增大,为单调递增函数,当y=2时,ylny = 2ln2 < 3ln2,当y=3时,ylny = 3ln3 >3ln2,结合单调性可知2