Answer:
[tex]3b^3y-6b^2cy+3c^3y-4b^3+8b^2c-4c^3[/tex]
Step-by-step explanation:
The given expression is
[tex](b-c)(b^2-bc-c^2)(3y-4)[/tex].
We expand the first two parenthesis to get,
[tex](b^3-2b^2c+c^3)(3y-4)[/tex]
We now expand again to get,
[tex]3y(b^3-2b^2c+c^3)-4(b^3-2b^2c+c^3)[/tex]
This will give us
[tex]3b^3y-6b^2cy+3c^3y-4b^3+8b^2c-4c^3[/tex]
