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    hey

    can someone please have a quick look over my working for this question and let me know where i've gone wrong cause i'm soo confused


    thank you
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    (Original post by Katiee224)
    ...
    The very first line - we have w = \frac{1}{z-2} \Rightarrow wz - 2w = 1.

    But you seem to be saying that wz - 2w = z(w-2), which isn't true!

    z(w-2) =zw -2z \neq zw - 2w.

    Instead, what you should have is

    \displaystyle 

\begin{equation*}z-2 = \frac{1}{w} = \frac{u-iv}{u^2 + v^2} \Rightarrow z = 2 + \frac{1}{w} =  \frac{2(u^2 + v^2)}{u^2 + v^2}+ \frac{u-iv}{u^2 + v^2}\end{equation*}
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    (Original post by Zacken)
    The very first line - we have w = \frac{1}{z-2} \Rightarrow wz - 2w = 1.

    But you seem to be saying that wz - 2w = z(w-2), which isn't true!

    z(w-2) =zw -2z \neq zw - 2w.

    Instead, what you should have is

    \displaystyle 

\begin{equation*}z-2 = \frac{1}{w} = \frac{u-iv}{u^2 + v^2} \Rightarrow z = 2 + \frac{1}{w} =  \frac{2(u^2 + v^2)}{u^2 + v^2}+ \frac{u-iv}{u^2 + v^2}\end{equation*}
    you saved the day once again zacken

    went through the problem again with your help and got the correct answer, i don't know how to avoid making these stupid mistakes in the exam, its really annoying
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    (Original post by Katiee224)
    you saved the day once again zacken

    went through the problem again with your help and got the correct answer, i don't know how to avoid making these stupid mistakes in the exam, its really annoying
    No worries, d'aaaw.

    I guess maybe slow down a bit and try and verify each step as you go through with it? Your handwriting is very pretty, by the way. :love:
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    (Original post by Zacken)
    Your handwriting is very pretty, by the way. :love:
    *ahem* DylanJ42 *ahem*
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    (Original post by Zacken)
    No worries, d'aaaw.

    I guess maybe slow down a bit and try and verify each step as you go through with it? Your handwriting is very pretty, by the way. :love:
    the problem is with fp2 as there is so much working out to each question :unimpressed:

    oh hehe erm thanks? would rather my working out was correct as apposed to pretty though
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    (Original post by Katiee224)
    the problem is with fp2 as there is so much working out to each question :unimpressed:

    oh hehe erm thanks? would rather my working out was correct as apposed to pretty though
    I guess just practice and it'll come naturally.

    Fair enough :lol:
 
 
 
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