Question

Daca B={x∈ IN/18 supra 2x+1∈ IN},atunci x∈{...}

Answer 1

2x+1/18 ⇒ 2x+1∈ D18⇒ 2x+1∈ {1,2,3,6,9,18}
⇒ 2x∈{0,1,2,5,8,17} ⇒x∈{0,1,4}⇒ B= {0,1,4}