In: Advanced Math
Consider G = (Z12, +). Let H = {0, 3, 6, 9}.
a. Show that H is a subgroup of G.
b. Find all the cosets of H in G and denote this set by G/H. [Note: If x ∈ G then H +12 [x]12 = {[h + x]12?? | [h]12 ∈ H} is the coset generated by x.]
c. For H +12 [x]12, H +12 [y]12 ∈ G/H define (H+12[x]12)⊕(H+12[y]12) by(H+12 [x]12)⊕(H+12 [y]12)=H+12 [x+y]12.
d. Show that ⊕ is well defined and construct the addition table for G/H with the operation ⊕.