题目内容
(1)3.14_________Q,0_________ N,2_________ Z,(-1)0_________ N,0_________;
(2)2__________{x|x<},3__________{x|x>4},+__________{x|x≤2+};
(3)3__________{x|x=n2+1,n∈N},5_________{x|x=n2+1,n∈N};
(4)(-1,1)_________ {y|y=x2},(-1,1)__________{(x,y)|y=x2}.
(1)0__________N; (2)-__________Q;
(3)__________Z; (4)__________R;
(5)|-3|__________N*; (6)0.5__________Z.