Q1 ∴ x=<1a_1 a_2 ...a_n >∈N & y=<a_1 a_2 ...a_n 1>∈N
if y=3x then , find the smallest
value of x
Q2 ∴ with the above conditions ,what other values
can be placed besides the number “ 1 ”
Let H be a non−empty subset of
a group G, prove that the follow−
ing are equivalent
1) H is a subgroup of G
2) for a,b ∈ H, ab^(−1) ∈ H
3) for a,b ∈ ab ∈ H
4) for a ∈ H, a^(−1) ∈ H
Hint: prove 1)→2)→3)→4)→1)
Help!!!