In: Advanced Math
Suppose G is a group and H and H are both subgroups of G.
Let HK={hk, h∈H and k ∈K}
a.give a example such that |HK| not equal to |H| |K|
b. give a example to show f :HK →H ⨯K given by f(hk) = (h,k) may not be well defined.
Here I'm taken a group Z12 under addition mod 12.and taken two subgroups H and K their multipicfmulti subgroup HK.and show all the parts .All answers are below thank you.