Here is the expression I'm supposed to find the product of:
$\displaystyle (4y^3+5y^2-12y)(-12-2)(7y^2-9y+12)$
To multiply it, does it matter whether or not I multiple a binomial with one of the trinomials first, or should I multiply the two trinomials together first? I can't seem to get it right. First I tried multiplying on eof the trinomials with the binomial:
$\displaystyle -12y(4y^3+5y^2-12y)-2(4y^3+5y^2-12y)$
which gave me $\displaystyle -48y^4+76y^3-10y^2+24$
I then multiplied that by the other trinomial,
$\displaystyle (7y^2-9y+12)$
which gave me $\displaystyle -336y^6+964y^5-1330y^4+1002y^3+48y^2-216y+288$
the correct answer is supposed to be $\displaystyle -336y^6-44y^5+974y^4-1854y^3+1392y^2+288y$
Thanks