Question

Determinati multimile: A={x e Z/ 6 supra x e Z} si B={x e Z / 15 supra x-1 e Z} va rog ajutati-ma scrieti detaliat totul adica toate rezolvarile va rog

Answer 1

A={x∈Z|6/x∈Z}
6/x∈Z⇒x∈D6
           x∈{1,2,3,-1,-2,-3}
A={1,2,3,-1,-2,-3}
B=x∈Z|15/x-1∈Z}
15/x-1∈Z⇒x-1∈D15
                 x-1∈{1,3,5,15,-1,-3,-5,-15}
                  x∈{2,4,6,16,0,-2,-4,-14}
 B=  {2,4,6,16,0,-2,-4,-14}