Algebra I – autumn 2024 – Homework 7
Find a direct product of well-known groups that is isomorphic to the quotient group (G, ·)/H
where
G =





1 0 0
a 1 0
c b r

 ; a, b ∈ Z, r ∈ {−1, 1}, c ∈ Z[i]



, H =





1 0 0
0 1 0
d + 2ei 2f 1

 ; d, e, f ∈ Z



.