用列举法表示下列集合:
(1){x|x+y=7,x∈N+,y∈N+};
(2){(x,y)|x+y=7,x∈N+,y∈N+};
(3){y|y=x2-1,-2<x<3,x∈Z}.
(1){1,2,3,4,5,6};
(2){(1,6),(2,5),(3,4),(4,3),(5,2),(6,1)}
(3){-1,0,3}.
用列举法表示下列集合:
(1){x|x+y=7,x∈N+,y∈N+};
(2){(x,y)|x+y=7,x∈N+,y∈N+};
(3){y|y=x2-1,-2<x<3,x∈Z}.
(1){1,2,3,4,5,6};
(2){(1,6),(2,5),(3,4),(4,3),(5,2),(6,1)}
(3){-1,0,3}.