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    Hi,
    Could someone help with this and explain each step? :

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    Thanks
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    (Original post by SuchBants)
    Hi,
    Could someone help with this and explain each step? :

    Name:  CodeCogsEqn.gif
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Size:  538 Bytes

    Thanks
    Hope that the attached document is enough explanation
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  1. File Type: pdf Scan0020.pdf (86.6 KB, 52 views)
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    (Original post by maggiehodgson)
    Hope that the attached document is enough explanation
    I get the common factor but where does the plus 1 come from.
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    (X-1)(3x-2) = 3x^2 - 2x - 3x + 2
    = 3x^2 - 5x + 2

    Expand the second bracket with the all elements (?) of the first bracket seperately. What you basically do when expanding this is x (3x-2) and -1 (3x-2) and then add the products of these together.

    I'm not good at explaining this but if you had another problem like (x^2-3x-2)(x-2), you would multiply x^2 (x-2) then -3x (x-2) & -2 (×-2) and add all products together to get the simplest form.

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    (Original post by SuchBants)
    I get the common factor but where does the plus 1 come from.
    The second term is (x-1) but this is really (x-1)times by 1

    if you were to factorise 3x^2 + x it would be x(3x + 1) because x is x times 1.

    Does that help?
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    (Original post by I'm_infires)
    (X-1)(3x-2) = 3x^2 - 2x - 3x + 2
    = 3x^2 - 5x + 2

    Expand the second bracket with the all elements (?) of the first bracket seperately. What you basically do when expanding this is x (3x-2) and -1 (3x-2) and then add the products of these together.

    I'm not good at explaining this but if you had another problem like (x^2-3x-2)(x-2), you would multiply x^2 (x-2) then -3x (x-2) & -2 (×-2) and add all products together to get the simplest form.

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    You seem to be explaining how to expand two brackets.

    But that's not what the OP asked.
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    1) factorise out (x-1):
    (x-1)[3(x-1) + 1]

    2) expand 2nd bracket
    (x-1)(3x-3+1) = (x - 1)(3x - 2)
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    (Original post by notnek)
    You seem to be explaining how to expand two brackets.

    But that's not what the OP asked.
    Yeah, I realised later on. It was because I couldn't see the maths question that the OP put a picture of so I thought that the pdf was the OP uploading the pic again or something but that was someone else :P
 
 
 
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