Well, I think that A ∩ B = 1 or 7 (Using Lagranges Theorem)
If A ∩ B is 1 it results in a contradiction because that would imply ord(AB)=49 > ord(G)
Which means that A ∩ B = 7
Which means the A = B ??
Homework Statement
Prove that a group of order 42 has a nontrivial normal subgroup
Homework Equations
We are supposed to use Cauchys Theorem to solve the problem
We are not allowed to use any of Sylows Theorems
The Attempt at a Solution
By using Cauchys Theorem i know there...