Prove the right and left cancellation laws for a group G tha
     Prove the right and left cancellation laws for a group G; that is, show that in the group G, ba = ca implies b = c and ab = ac implies b = c for elements a, b, c element G.  Show that if a^2 = e for all elements a in a group G, then G must be abelian. 
  
  Solution
31 ) Take two elements g,h which belong to G.
We know that (gh)^2 = e
and so you get
gh*gh = e.
Applying h to both sides on the right gives you
ghg hh = e.h = hg
Similarly , applying g to both sides :
gh gg = hg
gh = hg
Proving G is abelian

