8. Let G = GL2(R). (Tables are actually matrices)
(d) Determine whether A = {
} | a, b in R ) is a subgroup of G.
(e) Determine whether B = {
} | b, c in R ) is a subgroup of G.
(f) Determine whether C = {
} | d in R, d not equal 0) is a subgroup of G.
