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    2cx^2 +c (6a+b)x+3abc

    I know its pretty basic but I am having issues factorising this and its getting on my nerves!!

    The closest I get is:

    2cx(x+3a) + b(x+3a)

    I know it can be further simplified because that isnt the final answer and I am just not confident on the final steps - any help will be really appreciated.
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    (Original post by christinajane)
    2cx^2 +c (6a+b)x+3abc

    I know its pretty basic but I am having issues factorising this and its getting on my nerves!!

    The closest I get is:

    2cx(x+3a) + b(x+3a)

    I know it can be further simplified because that isnt the final answer and I am just not confident on the final steps - any help will be really appreciated.
    The first thing you can do is to take out a factor of c from everything. What is left is

    \displaystyle 2x^2 + (6a+b)x + 3ab

    which you can factor into linear factors in x.
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    (Original post by Zacken)
    That's great! Both these terms have a common factor of x+3a, if it helps, why don't you write u = (x+3a), then you have:

    \displaystyle 

\begin{equation*}2cx u + bu = u(2cx + b) = (x+3a)(2cx+b)\end{equation*}
    Isn't there a problem in OP's first step? Or have I misread it?
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    (Original post by christinajane)
    2cx^2 +c (6a+b)x+3abc

    I know its pretty basic but I am having issues factorising this and its getting on my nerves!!

    The closest I get is:

    2cx(x+3a) + b(x+3a)

    I know it can be further simplified because that isnt the final answer and I am just not confident on the final steps - any help will be really appreciated.
    See bolded. :-)

    (Original post by Gregorius)
    Isn't there a problem in OP's first step? Or have I misread it?
    Ah, yes. I assumed that the OP's first step was correct since it looked like the kind of method the question wanted. Having abc at the end makes it rather complicated for what I suspect the OP's level is at, perhaps a typo in the question?
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    (Original post by Zacken)
    Ah, yes. I assumed that the OP's first step was correct since it looked like the kind of method the question wanted. Having abc at the end makes it rather complicated for what I suspect the OP's level is at, perhaps a typo in the question?
    I don't think so; it comes out nice...
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    (Original post by Gregorius)
    I don't think so; it comes out nice...
    Ah, okay. I'll delete my post. Thanks!
 
 
 
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