(4m^2+6)(4m-6)=16m^3+24m-24m^2-36
(2x^2-x)(8x^2-2x)=16x^4-8x^3-4x^3+2x^2=16x^4-12x^3+2x^2
(a-4b)(a^2+3ab-6b^2)=a^3-4a^2b+3a^2b-12ab^2-6ab^2+24b^3= =a^3+a^2b-18ab^2+24b^3
-3c^3 (6-4c)(2c^2-9c)=(12c^4-18c^3)(2c^2-9c)=24c^6-36c^5-108-c^5+972c^4=
=24c^6-144c^5+972c^4