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Doubt about rotation isometry on the complex plane

  1. Nov 14, 2014 #1
    Dear All,
    In the 2nd paragraph of the attachment can you please explain to me why we are trying to make ## r(z) = z ##

    and what does "As r is not the identity........" mean??

    and how did the line ## L = 0.5*b + ρe^{θ/2} ## come about?


    Attached Files:

  2. jcsd
  3. Nov 15, 2014 #2


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    The second sentence starts "If (ii) Is true" so everything said here depends upon "(ii)" being true but we don't know what "(ii)" is!
  4. Nov 15, 2014 #3
    Oops sorry!!.

    The missing scan is in this attachement.


    Attached Files:

  5. Nov 21, 2014 #4


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    "r is not the identity" means "r is not the identity map", which means "r is not the unique function f such that f(z)=z for all z". So there's at least one complex number z such that r(z)≠z.
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