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group theory question

gp3.jpg

Need help on aiii

what does it mean by conjugate? or do I just power all of y by a?

Also can someone tell me if I got these right please.

ai) a b^-1 a^2 b a b a^-1

aii) b^-3 a^-1 b^-1 a
Reply 1
Original post by cooldudeman
gp3.jpg

Need help on aiii

what does it mean by conjugate? or do I just power all of y by a?

Also can someone tell me if I got these right please.

ai) a b^-1 a^2 b a b a^-1

aii) b^-3 a^-1 b^-1 a


Holy moly. Is that uni stuff?
Original post by Andy98
Holy moly. Is that uni stuff?


yep
Reply 3
Original post by cooldudeman
yep


No wonder I don't get it :lol:
Original post by cooldudeman

ai) a b^-1 a^2 b a b a^-1

aii) b^-3 a^-1 b^-1 a


Can't help with aiii - don't even know what yay^a means.

aii however is incorrect, try forming yy1yy^{-1} using that.

Recall (ab)1=b1a1(ab)^{-1}=b^{-1}a^{-1}
(edited 8 years ago)
Original post by cooldudeman
gp3.jpg

Need help on aiii



From a bit of digging I suspect you are looking for the element: aya1aya^{-1}

You should have a definition of the symbology in your notes somewhere.
(edited 8 years ago)
Original post by ghostwalker
From a bit of digging I suspect you are looking for the element: aya1aya^{-1}

You should have a definition of the symbology in your notes somewhere.


so aii is a b^-1 a^-1 b^-3 right?

and thanks for aiii, but I will ask my lecturer just in case.

For b, what does it mean by conjugate? I cannot for the life of me find the definition in my notes!
Original post by Andy98
Holy moly. Is that uni stuff?

Tots get you man :tongue: When a question barely makes sense :laugh:
Original post by cooldudeman
so aii is a b^-1 a^-1 b^-3 right?

and thanks for aiii, but I will ask my lecturer just in case.

For b, what does it mean by conjugate? I cannot for the life of me find the definition in my notes!


There's always Google.

Two elements x,y are conjugate if there exists an element, say a, such that ax=yaax=ya or putting it another way axa1=yaxa^{-1}=y, and I suspect with the notation used in your photo, that's y=xay=x^a
Original post by ghostwalker
There's always Google.

Two elements x,y are conjugate if there exists an element, say a, such that ax=yaax=ya or putting it another way axa1=yaxa^{-1}=y, and I suspect with the notation used in your photo, that's y=xay=x^a


so is it like aza^-1=z' = a^2 b^2 ab^-1 ab^-1 ?

Also for 3c, is it like we find aza^-1=z' and a^-1 za=z' and bzb^-1=z' and b^-1 zb=z'
??
Original post by cooldudeman
so is it like aza^-1=z' = a^2 b^2 ab^-1 ab^-1 ?


Well, at the end z has a^-1 already, so you'd end up with a^-2 at the end

aza1=z=a2b2ab1ab1a2aza^{-1}=z' = a^2 b^2 ab^{-1} ab^{-1}a^{-2}


Also for 3c, is it like we find aza^-1=z' and a^-1 za=z' and bzb^-1=z' and b^-1 zb=z'
??


I suspect so. Those are certainly conjugate, but:

Conjugacy is an equivalence relation, and you could do (ab)z(ab)1(ab)z(ab)^{-1} etc, but then there would be an infinite number of possibilities.

But since you're expected to list them all, that can't be the case.
I don't know what's expected there - I'd need to see some of the background material, or someone else may be familiar with this and more able to help.
Original post by ghostwalker
Well, at the end z has a^-1 already, so you'd end up with a^-2 at the end

aza1=z=a2b2ab1ab1a2aza^{-1}=z' = a^2 b^2 ab^{-1} ab^{-1}a^{-2}



I suspect so. Those are certainly conjugate, but:

Conjugacy is an equivalence relation, and you could do (ab)z(ab)1(ab)z(ab)^{-1} etc, but then there would be an infinite number of possibilities.

But since you're expected to list them all, that can't be the case.
I don't know what's expected there - I'd need to see some of the background material, or someone else may be familiar with this and more able to help.


Thanks at least for helping. I will ask around uni.

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