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Complex numbers

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    How do I express (z+i)* where (z+i)* is the complete conjugate of (z+i) and z = x + iy?
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    What's an expression for z+i? And how do you move from a complex number to it's conjugate?
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    (Original post by Slumpy)
    What's an expression for z+i? And how do you move from a complex number to it's conjugate?
    Not the kind of response I was looking for...
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    (Original post by Jooooshy)
    Not the kind of response I was looking for...
    Well, it's normally the kind of response you get. On here (particularly in Maths threads) we can either give you the answer or guide you there. Most people here prefer the latter, as at least you're coming the conclusion yourself and learning (also it avoids giving answers to homework cheaters).
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    (Original post by The Polymath)
    Well, it's normally the kind of response you get. On here (particularly in Maths threads) we can either give you the answer or guide you there. Most people here prefer the latter, as at least you're coming the conclusion yourself and learning (also it avoids giving answers to homework cheaters).
    Sorry, I thought you were being genuine. I have self-taught FP1, so I lack a lucid understanding...:-(

    Would (z+i) be x + i(y+1)? Then (z+i)* be x - i(y+1)?
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    (Original post by Jooooshy)
    Not the kind of response I was looking for...
    Well then you're on the wrong forum. The study help forum is for helping students learn, not giving them answers.
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    (Original post by Jooooshy)
    Sorry, I thought you were being genuine. I have self-taught FP1, so I lack a lucid understanding...:-(

    Would (z+i) be x + i(y+1)? Then (z+i)* be x - i(y+1)?
    It's been three months and I've already forgotten everything

    Sorry, I can't help you - I really need to quickly skim over the book again, this is just embarrassing...
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    (Original post by Jooooshy)
    Sorry, I thought you were being genuine. I have self-taught FP1, so I lack a lucid understanding...:-(

    Would (z+i) be x + i(y+1)? Then (z+i)* be x - i(y+1)?
    Yep that's right. Isn't it better when you manage it yourself?
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    (Original post by Jooooshy)
    Sorry, I thought you were being genuine. I have self-taught FP1, so I lack a lucid understanding...:-(

    Would (z+i) be x + i(y+1)? Then (z+i)* be x - i(y+1)?
    Yes.
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    (Original post by Intriguing Alias)
    Well then you're on the wrong forum. The study help forum is for helping students learn, not giving them answers.
    You obviously didn't read my post correctly. I didn't ask what the answer was, I asked how to do it.

    As for my reply, I thought he was seeking further guidance from me! I thought the user genuinely didn't know, reinforced by the profile description of 'No GCSEs. No A-levels.' which I later realised to be satirical. Give me a break.
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    (Original post by Intriguing Alias)
    Yep that's right. Isn't it better when you manage it yourself?
    Yes, although I wasn't 100% sure I understood how to do it! Thank you for the confirmation :-)
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    (Original post by Jooooshy)
    You obviously didn't read my post correctly. I didn't ask what the answer was, I asked how to do it.

    As for my reply, I thought he was seeking further guidance from me! I thought the user genuinely didn't know, reinforced by the profile description of 'No GCSEs. No A-levels.' which I later realised to be satirical. Give me a break.
    Oh no, it's totally true. I went to school in Scotland:p:
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    (Original post by Slumpy)
    Oh no, it's totally true. I went to school in Scotland:p:
    Ah, I see!

    Whilst you're online, would you care to check over another answer for me?

    The second part of the question is solve (z+i)* = 2iz + 1 giving your answer in the form a + bi

    Do I write z =... as my answer, or just the a + bi?

    I fiddled it down to simultaneous equations and got a = -1 and b = 1... Is this correct?
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    (Original post by Jooooshy)
    Ah, I see!

    Whilst you're online, would you care to check over another answer for me?

    The second part of the question is solve (z+i)* = 2iz + 1 giving your answer in the form a + bi

    Do I write z =... as my answer, or just the a + bi?

    I fiddled it down to simultaneous equations and got a = -1 and b = 1... Is this correct?
    Looks fine to me. I always tended to write down both, ie
    a=-1, b=1, so z=-1+i (doesn't take any time, and covers all bases)

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Updated: September 12, 2012
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