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    I was doing q6c on this paper and ran into a misunderstanding

    QP: https://07a69ccf283966549a9350d1a669...%20Edexcel.pdf

    surely we square and cube everything inside the bracket of the g(x) function? (as shown in the image i uploaded)


    can someone explain why this is wrong, the x value in the g(x) function is 2x so surely we square and cube that?





    Zacken
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    (Original post by Katiee224)
    Zacken
    No, the x value is x. That's all you're changing.

    If it helps, you could write it as g(x) = ln 2 + ln x.

    So g(x^2) = ln 2 + ln x^2 = ln (2x^2).
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    (Original post by Zacken)
    No, the x value is x. That's all you're changing.

    If it helps, you could write it as g(x) = ln 2 + ln x.

    So g(x^2) = ln 2 + ln x^2 = ln (2x^2).
    2 minute wait for a reply zacken, you're slacking


    ah ok I see now, what if we had '2y' in the bracket, so

    g(x) = ln(2y)

    and wanted to work out g(x^2)?

    or is that not possible as it has to be a function of x?
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    (Original post by Katiee224)
    2 minute wait for a reply zacken, you're slacking


    ah ok I see now, what if we had '2y' in the bracket, so

    g(x) = ln(2y)

    and wanted to work out g(x^2)?

    or is that not possible as it has to be a function of x?
    Well, yeah. Then y is basically just a constant instead of a variable, so g(x) = g(x^2) = g(x^elephant) = ln(2y).

    (basically what you said about it having to be a function of x)
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    (Original post by Zacken)
    Well, yeah. Then y is basically just a constant instead of a variable, so g(x) = g(x^2) = g(x^elephant) = ln(2y).

    (basically what you said about it having to be a function of x)

    hahaha okay thanks for the help, btw do you recommend doing TeeEm's papers for c3/c4 revision or get the edexcel past papers done first?

    how have you been revising for these subjects?
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    (Original post by Katiee224)
    hahaha okay thanks for the help, btw do you recommend doing TeeEm's papers for c3/c4 revision or get the edexcel past papers done first?

    how have you been revising for these subjects?
    Get the Edexcel papers done first.

    I did them in Jan.
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    (Original post by Zacken)
    Get the Edexcel papers done first.

    I did them in Jan.
    haha you cocky lil :laugh:

    did you get 100 UMS in all of them I'm guessing?
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    (Original post by Katiee224)
    haha you cocky lil :laugh:

    did you get 100 UMS in all of them I'm guessing?
    Something like that.

    I'm sure you'll do fine!
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    (Original post by Zacken)
    Something like that.

    I'm sure you'll do fine!
    Gotta let me know your maths results when you get them, so I can stare at your UMS in envy
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    (Original post by Katiee224)
    Gotta let me know your maths results when you get them, so I can stare at your UMS in envy
    It's nothing special. :lol: UMS sucks anyway.
 
 
 
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