posted by Anonymous .
if n=45, calculate the number of cosets of An in Sn .
Your question makes no sense to me.
I'm not really sure about this, but I'll give it a go. By the way, what do you mean by cosets?
Solving for the number of (costs?) of An in Sn.
This is the most I can simplify it down to. If you post the full question from wherever you're getting it from, I may just be able to help.
Answer is 2..
From Lagrange's Theorem, we know that the number of cosets in An in Sn is [Sn:An] = |Sn|/|An| = 2
Note An = n!/2 = |Sn|/2