- #1
rakalakalili
- 14
- 0
Homework Statement
If G is a group, and H and K are subgroups of G, prove:
[tex]|HK|=\frac{|H||K|}{|H\cap K|}[/tex]
Homework Equations
The Attempt at a Solution
A basic counting argument can be made by saying that HK consists of an element of H with an element of K, so you have |H||K| elements. What I don't quite see is how this creates over counting by a factor of |H n k|. A hint would be much appreciated!