This preview shows page 1. Sign up to view the full content.
Unformatted text preview: { ( 2 a , 2 b )  a , b Z } (c) { ( 2 a , )  a Z } (d) { ( a ,a )  a Z } Let the relevant set of elements be I . (a) No. For example ( 1 , 1 ) I , but ( 1 , 1 )( 1 , ) / I . (b) Yes. 0 I and I is closed under +. Finally if ( x , y ) Z Z , then ( 2 a , 2 b )( x , y ) = ( 2 ax , 2 by ) I . (c) Yes. 0 I and I is closed under +. Finally if ( x , y ) Z Z , then ( 2 a , )( x , y )=( 2 ax , ) I . (d) No. For example ( 1 ,1 ) I , but ( 1 ,1 )( 1 ,1 ) = ( 1 , 1 ) / I ....
View Full
Document
 Spring '08
 Staff
 Math, Algebra

Click to edit the document details