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Math Help - multiplying binomial w/two trinomials

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    multiplying binomial w/two trinomials

    Sorry, I figured it out; I'd like to delete the thread can't seem to delete right now though.
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    Quote Originally Posted by greatsheelephant View Post
    Here is the expression I'm supposed to find the product of:
    (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:
    -12y(4y^3+5y^2-12y)-2(4y^3+5y^2-12y)
    which gave me -48y^4+76y^3-10y^2+24
    I then multiplied that by the other trinomial,
    (7y^2-9y+12)
    which gave me -336y^6+964y^5-1330y^4+1002y^3+48y^2-216y+288

    the correct answer is supposed to be -336y^6-44y^5+974y^4-1854y^3+1392y^2+288y

    Thanks
    -12-2 = -14 so that's the middle bracket sorted. Also you can take a factor of y from the first set.

    -14y(4y^2+5y-12)(7y^2-9y+12)

    Since this gives a polynomial of order 5 whereas the book says order 6 I suspect you've made a typo in the original question. Probably the middle bracket
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