问题
选择题
已知M={x2,2x-1,-x-1},N={x2+1,-3,x+1},且M∩N={0,-3},则x的值为( )
A.-1
B.1
C.-2
D.2
答案
∵M∩N={0,-3},
∴0∈N
∵x2+1≥1
∴x+1=0解得x=-1
当x=-1时,M={1,-3,0} N={2,-3,0}满足题意
故选A
已知M={x2,2x-1,-x-1},N={x2+1,-3,x+1},且M∩N={0,-3},则x的值为( )
A.-1
B.1
C.-2
D.2
∵M∩N={0,-3},
∴0∈N
∵x2+1≥1
∴x+1=0解得x=-1
当x=-1时,M={1,-3,0} N={2,-3,0}满足题意
故选A