$\displaystyle (4y^3)^3 \div 2y^3 $
$\displaystyle 4y^9 \div 2y^3 $
$\displaystyle 4 \div 2 = 2 $ $\displaystyle y^9 \div y^3 = y^6 $
$\displaystyle 2y^6 $
is this working right? Because my book says the correct answer is $\displaystyle 32y^6 $ and I dont understand were 32 came from ?