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    Does anyone know how to do this Q by finding max arg(z)

    Given that |z - 5 + 7i| = 5

    I've drawn it on an argand diagram but still not sure how to work out max arg(z)

    Any help would be greatly appreciated. Thanks.
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    (Original post by abdul h)
    Does anyone know how to do this Q by finding max arg(z)

    Given that |z - 5 + 7i| = 5

    I've drawn it on an argand diagram but still not sure how to work out max arg(z)

    Any help would be greatly appreciated. Thanks.
    Draw a line from the origin to the circle such that it touches the circle and the argument between that line and the x-axis is greatest. Mark that angle \theta and this is what you want to find.
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    (Original post by RDKGames)
    Draw a line from the origin to the circle such that it touches the circle and the argument between that line and the x-axis is greatest. Mark that angle \theta and this is what you want to find.
    By drawing a tangent from origin to touching the circle when theta is greatest. Wouldn't arg(z) be found by measuring anticlockwise by
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    (Original post by abdul h)
    By drawing a tangent from origin to touching the circle when theta is greatest. Wouldn't arg(z) be found by measuring anticlockwise by
    What?
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    (Original post by RDKGames)
    What?
    Sorry I was meant to say measuring anti-clockwise from positive real axis.
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    (Original post by abdul h)
    Sorry I was meant to say measuring anti-clockwise from positive real axis.
    Yes it would be, but you need to find it's exact value.
 
 
 
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