Question

Aflati produsul elementelor multimii A={x e Z | 18 supra 2x-1 e N}

Answer 1

D18={1;2;3;6;9;18}. 2x-1=1 => x=1;;2x-1=2 => x=3/2( nu apartine lui z);;2x-1=3 => x=2;; 2x-1=6 => x=7/2( nu apartine lui z);;2x-1=9 => x=5; 2x-1=18 => x=19/2( nu apartine lui z) => produsul=1*2*5=10