Express the expression? Math problem

Express the expression:
3 log(b) z - (1/2)(log(b) x+log(b) y) as a single logarithm. Assume all variables represent positive real numbers.

3 log(b) z - (1/2)(log(b) x+log(b) y)=log(b)z³-log(b)√x -log(b)√y
=log(b)[z³/√(xy)]

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