# prove

• November 24th 2008, 11:10 AM
mandy123
prove
Prove that there is no homomorphism from Z_8 (+) Z_2 onto Z_4 (+) Z_4

[(+) is the external direct product]

(Crying)
• November 24th 2008, 07:15 PM
ThePerfectHacker
Quote:

Originally Posted by mandy123
Prove that there is no homomorphism from Z_8 (+) Z_2 onto Z_4 (+) Z_4

[(+) is the external direct product]

(Crying)

Hint: Any homomorphism is determined by $f( 1,1)$.
Try to arrive to a contradiction.