fp2 question

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  1. lubus's Avatar
    1 17-06-2012  18:01
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    fp2 question
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    im just wandering, when i get to the line |w-2 | = | -1+2w |

    cant i just square everything, getting

    w^2 +4 = 1 + 4w^2

    3 = 3w^2

    1 = w^2

    root,and put modulus on both sides.. 1 = | w |
  2. snow leopard's Avatar
    2 17-06-2012  19:02
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    Re: fp2 question
    Squaring each term isn't a legitimate way of removing the modulus, this method works by luck.
    Last edited by snow leopard; 17-06-2012 at 19:05.
  3. aznkid66's Avatar
    3 17-06-2012  19:37
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    Re: fp2 question
    If you think about it, squaring each term isn't equivalent to squaring the real and complex parts.

    For example:
    \|k+a+bi\|=\sqrt{(k+a)^2+b^2} \not =\sqrt{k^2+a^2+b}

    Like snow said, you got lucky.
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