用符号“∈”或“∉”填空..
问题描述:
用符号“∈”或“∉”填空..
(1)若A={X|X²=X},则-1____A
(2)若B={X|X²+X-6=0},则3____B
(3)若C={X∈N|1≤X≤10},则8______C
(4)若D={X∈Z|-2<X<3},则1.5____D
答
(1)若A={X|X²=X},则-1__∉__A
(2)若B={X|X²+X-6=0},则3__∉__B
(3)若C={X∈N|1≤X≤10},则8___∈___C
(4)若D={X∈Z|-2<X<3},则1.5__∉__D