来自黄永清的问题
用合适的符号填空:(1)5-2___R,16___Z(2)N___{0,1},Q___N(3)-1___{x|x2=-1},-2___{x|x2-6x+8=0}
用合适的符号填空:
(1)
5-
2___R,
16___Z
(2)N___{0,1},Q___N
(3)-1___{x|x2=-1},-2___{x|x2-6x+8=0}
(4)∅___{x|x2+3=0},∅___R
(5){2}___{x|x2-4=0},Z___R.
1回答
2020-04-30 22:49