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factor theorem question Watch

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    factor theorem question:

    -4x^3+8x^2+29x+12

    I got (x-4)(2x+3)-2(x+1) but think its wrong lol could someone work it out, cheers
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    I can tell immediately it isn't correct:

    Keep everything in brackets:

    (x-4)(2x+3)(-2x-2)

    (-4)(3)(-2) is 24, not 12

    So not correct I'm afraid. Quick and easy way to start testing if you've got it correct is to check if you can multiple out the highest power and number terms by themselves. In this case the -4x^3 and 12. The -4x^3 works but the 12 doesn't so you've made a mistake somewhere.

    If you've got your working drop it here and myself or someone else can point out where you went wrong.
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    Acsel here is working out Name:  IMG_4970.jpg
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    (Original post by DeCosta)
    Acsel here is working out Name:  IMG_4970.jpg
Views: 30
Size:  507.9 KB
    That looks correct. Do you have the working for factorising the quadratic at the end? That seems to be where the issue is

    EDIT: You aren't far off actually, you have most of the right numbers, just some issues with the operations and not having it fully factorised
 
 
 
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