1. If x is an element of a group and x is of order n then the elements 1, x, x^2,...x^n-1 are distinct (don't know how to show this!)
2. Let Y= Y here is a group show
a) v^2=v^-1
b) v commutes with u^3
c) v commutes with u
d) uv=1
e) u=1, deduce that v=1 and conclude that Y=1