solve by using polynomial division(16ab^3c-10ab^2c^2+12a^2b^2c/(4a^2b)

i always get 4b^2-2b+3b+-2c^3/4a^b

You can only factor 2 out of the coefficients in the numerator.

Then you can only factor ab out of the variables, leaving

(8b^2c - 5bc^2 + 6abc)/2a