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    https://jacktilson.net/edu/maths/mar...ummer-2005.pdf
    If you go to page 26 , to question 7b! How do they get the final answer of u^2+v^2=1/2
    Ive done everything on top but i cant seem to get the final answer tbh?
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    (Original post by English-help)
    https://jacktilson.net/edu/maths/mar...ummer-2005.pdf
    If you go to page 26 , to question 7b! How do they get the final answer of u^2+v^2=1/2
    Ive done everything on top but i cant seem to get the final answer tbh?
    Since they have the same denominator, you can add the fractions to get

    \displaystyle \frac{u^2+v^2}{\left(u^2+v^2 \right)^2} = 2

    Now try cancelling the fraction.
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    (Original post by notnek)
    Since they have the same denominator, you can add the fractions to get

    \displaystyle \frac{u^2+v^2}{\left(u^2+v^2 \right)^2} = 2

    Now try cancelling the fraction.
    Ohhh yeahh , so simple , my brain :facepalm:
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    Thank you , much appreciated
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    I don't do FM, so sorry if this is a stupid question, but why you do include the v's on the bottom when taking the real part and include the u's when taking the imaginary part?
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    (Original post by h3rmit)
    I don't do FM, so sorry if this is a stupid question, but why you do include the v's on the bottom when taking the real part and include the u's when taking the imaginary part?
    Do you mean top? You may need to clarify what you mean.
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    (Original post by notnek)
    Do you mean top? You may need to clarify what you mean.
    On the second line, the v's are included in the bottom part (u^2 + v^2). But since they're the imaginary component , why are they included in the real part (and viceversa for the imaginary part and u's)
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    (Original post by h3rmit)
    On the second line, the v's are included in the bottom part (u^2 + v^2). But since they're the imaginary component , why are they included in the real part (and viceversa for the imaginary part and u's)
    You don't do FM so I'm not sure what you know / don't know.

    Basically in the working they have reached this complex number:

    \displaystyle \frac{u-iv}{u^2+v^2}

    where u and v are real numbers. By splitting the fraction you can rewrite this:

    \displaystyle \frac{u}{u^2+v^2} - \frac{iv}{u^2+v^2} = \frac{u}{u^2+v^2}- \left(\frac{v}{u^2+v^2}\right)i

    So the real part of this complex number is \displaystyle \frac{u}{u^2+v^2} and the imaginary part is \displaystyle \frac{-v}{u^2+v^2}.
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    (Original post by notnek)
    You don't do FM so I'm not sure what you know / don't know.

    Basically in the working they have reached this complex number:

    \displaystyle \frac{u-iv}{u^2+v^2}

    where u and v are real numbers. By splitting the fraction you can rewrite this:

    \displaystyle \frac{u}{u^2+v^2} - \frac{iv}{u^2+v^2} = \frac{u}{u^2+v^2}- \left(\frac{v}{u^2+v^2}\right)i

    So the real part of this complex number is \displaystyle \frac{u}{u^2+v^2} and the imaginary part is \displaystyle \frac{-v}{u^2+v^2}.
    Ah, I was tforgetting v was a real number for some reason, never mind. Cheers
 
 
 
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