(ac)^2(2b+3c)^2-ab^2(3c+2b)
=a^2c^2(2b+3c)^2-ab^2(3c+2b)
=a(2b+3c)[ac^2(2b+3c)-b^2]
=a(2b+3c)(2abc^2+3ac^3-b^2)