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    Um, I'm a bit rusty with my factorisation skills but can someone show me how I should factorise this please?

    7u² - 8u + 1 = 0
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    You coulde use the Quadratic formula or
    Put the 7u and u in brackets find something that times together to make 1 so that would be 1X1, then put in the signs
    (7u-1)(u-1)
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    (Original post by sunny_veggies)
    You coulde use the Quadratic formula or
    Put the 7u and u in brackets find something that times together to make 1 so that would be 1X1, then put in the signs
    (7u-1)(u-1)
    Wrong, that is used to solve the equation not to factorise.
    True
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    Find two numbers that have multiply to make 7 and add to make -8, which are -7, -1, so you get

    7u² - 7u-1u + 1 = 0

    then factorise 7u^2 - 7u, and -1u + 1, then you should know what to do if you are being truthful about ur A* in maths
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    (Original post by jit987)
    Wrong, that is used to solve the equation not to factorise.
    True
    Ahhh I see what I did wrong...

    The actual question I was doing was solving the equation of:

    7^2x+1 - 8 x 7^x + 1 = 0 where u = 7^x

    and i got to 7u² - 8u + 1 = 0, and when I factorised I got 1, and 1/7

    I was doing the question out of the book, and checked for answers at the back, and saw 0, and -1, and was thinking I factorised wrong, but it was just me forgetting the last bit of:

    7^x = 1, x = 0

    7^x = 1/7
    x = -1

    Anyway thanks guys
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    (Original post by jit987)
    Wrong, that is used to solve the equation not to factorise.
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    No its not, you can work back from those answers and put them into brackets, i wouldnt personally do it that way but you can
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    (Original post by Extricated)
    Find two numbers that have multiply to make 7 and add to make -8, which are -7, -1, so you get

    7u² - 7u-1u + 1 = 0

    then factorise 7u^2 - 7u, and -1u + 1, then you should know what to do if you are being truthful about ur A* in maths
    Yes I did get an A* in Maths GCSE lol xD, and look at my above post
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    (Original post by EternalDoom)
    Yes I did get an A* in Maths GCSE lol xD, and look at my above post
    LOL anytime
 
 
 
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