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    Hi,

    If we have arg(z/z+3) = pi/4 then we draw a circe above the x axis from 0 to -3

    however, for arg (z-3i/z-5) it is below the axis.

    How do you find out whether to draw above or below?

    Thanks
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    Go from top to bottom, anticlockwise IRC. I.e go from coord at the top of the fraction to the coord on the bottom, anticlockwise.
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    (Original post by bananarama2)
    Go from top to bottom, anticlockwise IRC. I.e go from coord at the top of the fraction to the coord on the bottom, anticlockwise.
    But why?
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    (Original post by David_Skiller)
    But why?
    Takes a bit of practice, if we draw \arg{\frac{z}{z + 3}} = \frac{\pi}{4}, then \arg{z} - \arg{(z + 3)} = \frac{\pi}{4}. So by this, we know that \arg{z} must be greater than \arg{(z + 3)} and in some cases \arg{(\frac{a}{b})} = \alpha must go below the axis for \arg{a}to be greater than \arg{b}


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    (Original post by David_Skiller)
    But why?
    I don't know :/ I hate loci that much I just didn't want to know
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    (Original post by David_Skiller)
    But why?
    (Original post by bananarama2)
    I don't know :/ I hate loci that much I just didn't want to know
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