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    Hi, I'm having a problem with proving that the associative th property and finding an identity element for this?
    Any help will be much appreciated
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    DFranklin
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    (Original post by maths10101)
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    Hi, I'm having a problem with proving that the associative th property and finding an identity element for this?
    Any help will be much appreciated
    I'm not DFranklin or Ghostwalker, but I'll have a bash anyway:

    Associativity: Let's compute:

    \displaystyle 

\begin{equation*}(a * b) * c = \left(a + (-1)^a b\right) * c = a + (-1)^a b + (-1)^{a + (-1)^a b}c\end{equation*}

    Now let's do:

    \displaystyle 

\begin{equation*}a * (b*c) = a * \left(b + (-1)^b c\right) = a + (-1)^{a} \left(b + (-1)^{b}c\right)\end{equation*}

    Now try expanding the above out and using your indices rule to show that it's the same as the first equation.

    Does this help?
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    (Original post by Zacken)
    I'm not DFranklin or Ghostwalker, but I'll have a bash anyway:

    Associativity: Let's compute:

    \displaystyle 

\begin{equation*}(a * b) * c = \left(a + (-1)^a b\right) * c = a + (-1)^a b + (-1)^{a + (-1)^a b}c\end{equation*}

    Now let's do:

    \displaystyle 

\begin{equation*}a * (b*c) = a * \left(b + (-1)^b c\right) = a + (-1)^{a} \left(b + (-1)^{b}c\right)\end{equation*}

    Now try expanding the above out and using your indices rule to show that it's the same as the first equation.

    Does this help?
    Hi yeah, that's great thanks! I got the answer in the end and comparing my work to yours has made me certain it's correct...thanks!
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    (Original post by maths10101)
    Hi yeah, that's great thanks! I got the answer in the end and comparing my work to yours has made me certain it's correct...thanks!
    Do you still need help with the identity, or...?
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    (Original post by Zacken)
    Do you still need help with the identity, or...?
    Nah that's fine, I got the identity as being 0 bro
 
 
 
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