What is 1 / 3 × A2 & # 178; B & # 179; - A & # 178; B & # 178; equal to?

What is 1 / 3 × A2 & # 178; B & # 179; - A & # 178; B & # 178; equal to?

1/3×a²b³-a²b²
=1/3a²b²(b-1)