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    Hello there,
    I know the explanation is simple, but I've been having a mental block !

    Suppose we are working with Z/5Z (where Z is the set of integers).

    Why is it that [1] / [2] gives [3] ??? And why does [2] / [2] give [4] ????

    I cant remember how you work these out?

    Any help would be much appreciated.
    Thank you for your time.
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    Finding [1] / [2] is the same as solving 2x = 1 (mod 5).
    Finding [2] / [2] is the same as solving 2x = 2 (mod 5).

    It is easy to check which of the five possible values of x (0, 1, 2, 3, 4) is a solution.

    For more complicated problems, Euclid's algorithm will solve the mod equations.
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    ok cool, that makes sense :

    But then, why does [2]/[2] give [4] ??

    If this [2]/[2] is equivalent to solving 2x = 2mod5, then 5 must be a factor of 2x - 2. But if x = 4, then 5 is a factor of 6, which is not true :confused:

    cheers Jonny
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    It doesn't give [4], it gives [1].
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    thanks Mike,

    yeah that's what I thought!!

    There's an example in my notes which is wrong (or I must have copied down wrong haha).

    Cheers mate!!
 
 
 
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Updated: April 13, 2006
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