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    https://8dedc505ac3fba908c50836f5905...%20Edexcel.pdf

    On this paper question 5 part c, why aren't we supposed to make z the subject and sub in w=u+iv as is the standard protocol for a question like this?

    It is saying "A transformation T from the z-plane to the w-plane is given by"




    For example on question 1 in this paper we are also solving a problem where we are putting the imaginary part = 0, but here they have done it the other way of putting z as the subject, why is it any different to this quesiton?
    https://8dedc505ac3fba908c50836f5905...%20Edexcel.pdf


    I hope I'm making sense :laugh:

    would appreciate any help


    Zacken any ideas? :P
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    (Original post by Katiee224)
    https://8dedc505ac3fba908c50836f5905...%20Edexcel.pdf

    On this paper question 5 part c, why aren't we supposed to make z the subject and sub in w=u+iv as is the standard protocol for a question like this?

    It is saying "A transformation T from the z-plane to the w-plane is given by"
    Because we want to show something about z. If we re-arrange for z and then sub in u + iv, then we'll know something about the locus of w.

    In this question:

    We are told that Q (in the z plane) is mapped to R (in the w plane) and we are given information about R (in the w plane) and told to find information about Q (in the z plane).

    In the other question:

    We are told that Q (in the z plane) is mapped to R (in the w plane) and we are given information about Q (in the z plane) and told to find information about R (in the w plane)

    I've used the "Q and R" in the second question even if it's not given in the question to highlight the differences. But in the second example, Q means "points on the real axis in the z-plane" and R means "line in the w-plane".
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    (Original post by Zacken)
    Because we want to show something about z. If we re-arrange for z and then sub in u + iv, then we'll know something about the locus of w.

    In this question:

    We are told that Q (in the z plane) is mapped to R (in the w plane) and we are given information about R (in the w plane) and told to find information about Q (in the z plane).

    In the other question:

    We are told that Q (in the z plane) is mapped to R (in the w plane) and we are given information about Q (in the z plane) and told to find information about R (in the w plane)

    I've used the "Q and R" in the second question even if it's not given in the question to highlight the differences. But in the second example, Q means "points on the real axis in the z-plane" and R means "line in the w-plane".
    Aww I thought it was something along those lines but that clarifies it for me, thank you

    ps you never replied to my last pm I hope your revision's going better than mine
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    (Original post by Katiee224)
    Aww I thought it was something along those lines but that clarifies it for me, thank you

    ps you never replied to my last pm I hope your revision's going better than mine
    No problem.

    Oh, I didn't? I'm sorry! I must have forgotten. :facepalm: It's going so-so, yours? I've pretty much just stopped all A-Level revision and I'm going all out on STEP atm so not looking forward to Physics in 6 days time... you?
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    Hi, does anyone know how to represent the line 2x + y = 5 in the complex plane? Thanks!
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    (Original post by mhardikar)
    Hi, does anyone know how to represent the line 2x + y = 5 in the complex plane? Thanks!
    z=x+{\bf i}(5-2x) for x\in \mathbb{R}

    This is assuming you want your y-axis as the imaginary one and the x-axis as your real line??
 
 
 
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