In: Advanced Math
Algebraists have proven (using more advanced techniques than ones we’ve discussed) that An is a simple group for n ≥ 5.
Using this fact, prove that for n ≥ 5, An has no subgroup of order n!/4 .
c) Prove that Sn is not simple for n ≥ 3.
d) Is GL(2, R) a simple group? Prove your claim.