Matrix Representation of Permutations: (1874)(36759)

[Punkyc7]

Write the following in two row matrix form.


(1874)(36759)



I have

[1 2 3 4 5 6 7 8 9]
[8 2 6 1 9 7 4 7 3]

my problem is couldn't 7 also go to 5 and have 8 going to 7 and 6 going to 7 so I am sure I am wrong but I am not sure why.

 

[micromass]

With (1874)(36759) they mean the COMPOSITION of two permutation. So you first need to apply (36759) and then (1874). So you first need to work out the composition before you write down the matrix.

 

[Punkyc7]

oh that would make more sense. So how would I go about doing that.

would I say that
3->6
6->7
5->9
9->3

then
1->8
8->7
7->4
4->1

and since 6->7 and 7-> 4 I can say 6->4

[1 2 3 4 5 6 7 8 9]
[8 2 6 1 9 4 ? 7 3] and since 5 hasnt been used would I just stick it into get 7->5


[1 2 3 4 5 6 7 8 9]
[8 2 6 1 9 4 5 7 3]

Is that right?

 

[micromass]

would I say that
3->6
6->7
5->9
9->3

You forgot to put 7->5 here. You can read that off (1874)(36759)

[1 2 3 4 5 6 7 8 9]
[8 2 6 1 9 4 5 7 3]

Is that right?

Yes.

 

[Punkyc7]

oops... Thank you.