Prove that if H and K are two solvable normal subgroup of G then HK is also solvable normal subgroup of G.
I proved that every (H i K i ) is a normal subgroup of (H i+1 K i+1 ) but now I am struck in proving that Factors of Normal series of HK are abelian
I don't see a solution to the second, so while it is a duplicate, it doesn't help OP.
I agree we should avoid duplicates.
– NewViewsMath Nov 22 '24 at 21:07