Odd-order and ambivalent implies trivial
Statement
Suppose is an Odd-order group (?) (i.e., a finite group of odd order) that is also an Ambivalent group (?): every element is conjugate to its inverse. Then,
is the trivial group.
Facts used
Proof
Suppose has odd order, is ambivalent, and is nontrivial. Then, there exists a non-identity element
in
. By fact (1),
has odd order, so
.
Since is ambivalent, there exists
such that
. Then,
, so
and
commute. Again by fact (1),
has odd order, so
. Since
commutes with
, it must commute with all elements in
, and hence with
. Thus,
. This forces
, a contradiction.