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The 2010, Honorary Member Welcoming, Undergraduate Degree Results Chat Thread Mk. V Watch

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    (Original post by + polarity -)
    It's when |ax| < 1

    Where a is -1/3 (you take the 3 out) to put the stuff in the brackets in the form (1 + ax)n
    Ahh right, so in my case its |-x| &lt; 1\Rightarrow \ |x| &lt; -1?
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    (Original post by Loz17)
    :rofl: Yep :p:

    I gave up after the xmas hols, as you can see. I got like 17 marks in my mock though

    Anyone know how to work out the range of which an expansion is valid?

    Spoiler:
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    The Expansion in question is(3-x)^{-4}
    (3-x)^{-4}

    =3^{-4}(1-\frac{x}{3})^{-4}

    which meeeeeeeannnnsss:

    |\frac{x}{3}|&lt;1
    so
    |x|&lt;3


    I think....
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    (Original post by Loz17)
    Ahh right, so in my case its |-x| &lt; 1\Rightarrow \ |x| &lt; -1?
    What max said , but I think it's safer to leave it as |x/3| < 1
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    (Original post by maxfire)
    (3-x)^{-4}

    =3^{-4}(1-\frac{x}{3})^{-4}

    which meeeeeeeannnnsss:

    |\frac{x}{3}|&lt;1
    so
    |x|&lt;3


    I think....
    Oh right, I forgot about the 3 :facepalm: *does whole question again, thinking shes gonna fail and not get this finished :emo:*

    Thanks both of you
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    Shiz. Is it even worth napping now? I'm so tired, but it's late.
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    Nahh, just get an early night :yep:
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    (Original post by + polarity -)
    Shiz. Is it even worth napping now? I'm so tired, but it's late.
    Yeah, go for it. Or just get a bit longer during the night.
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    (Original post by maxfire)
    Yeah, go for it. Or just get a bit longer during the night.
    Okay, I'll go soon.
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    Hmm...what should I snack on?
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    :lurk:
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    food innit :yum:
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    Wait... I'm starting to feel less tired! Maybe I should just wait!
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    you should all leave now until the next page :yep:
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    :work:
    • Thread Starter
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    Anon wants to spam :p:
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    yes....i want to spam :ninja:
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    i know you're there max :hmmm:
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    Omg. Plz.
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    1,000

    :yeah:
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    **** it
 
 
 
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