MASTER'S THEOREM :
Let f be an increasing function that satisfies the recurrence relation
f(n) = af(n/b) + cnd
whenever n = bk, where k is a positive integer, a ≥ 1, b is an integer greater than 1, and c
and d are real numbers with c positive and d nonnegative. Then f(n) is:
1) O(nd ) if a < bd ,
2) O(nd log n) if a = bd ,
3) O(nlogb a) if a > bd .
now for given question, comparing by standard form, gives c = logn (a function of n) while according to the theoram it should be a constant value...
So we cannot apply the Master's Theoram in the given question...