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Thread: Factoring{resolved}

  1. #1

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    Question Factoring{resolved}

    Once again i am having trouble factoring. Problem is that somtimes i don't know how to first approach a problem.

    4x4 - 24x3 + 32x2

    Now is this a product of two bionominals? I keep wanting to do this. 4x(x3 - 6x2 + 8x) Which is incorrect.

  2. #2
    vbuggy krtxmrtz's Avatar
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    Why is this incorrect? In any case what you can do is factorize it further, something like
    4x2(x2 - 6x + 8)

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  4. #4
    vbuggy krtxmrtz's Avatar
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    Originally posted by Dilenger4
    It should end up being 4x2(x-4)(x-2)
    Well, you got it already. What else are you supposed to do? The way to arrive at this final factorization is by solving -calculating the roots- of the 2nd degree equation.

    I suppose you know how to solve an equation such as

    ax2 + bx + c = 0

    Once you've found the roots (let these be p and q) you can rewrite it as

    (x - p)(x - q) = 0

  5. #5

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    I didn't get it. The answer came from another source.

    Further clarification is needed.

    This is how i end up solving this problem which is incorrect.

    6a2 - 18a -24

    (2a - 8)(3a + 3)
    6a2 + 6a -24a -24
    6a2 -18a -24

    It should be.

    6a2 -18a -24

    6(a - 4)(a + 1)
    6(a2 + a -4a -4)
    6(a2 -3a -4)
    6a2 - 18a -24

    So my question is. If i end up getting (2a - 8)(3a + 3) can i somehow figure out how to get 6(a - 4)(a + 1)?

  6. #6
    Fanatic Member bugzpodder's Avatar
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    (2a - 8)(3a + 3)

    2a-8=2(a-4)
    3a+3=3(a+1)

    hence (2a-8)(3a+3)=(2(a-4))(3(a+1))=2(a-4)3(a+1)=6(a-4)(a+1)
    Massey RuleZ! ^-^__Cheers!__^-^ Massey RuleZ!


    Did you know that...
    The probability that a random rational number has an even denominator is 1/3 (Salamin and Gosper 1972)? This result is independently verified by me (2002)!

  7. #7

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    Couldn't be clearer.



    Thanks bugzpodder

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