问题
选择题
已知a,b∈R,则“b≥0”是“a2+b≥0”的( )
A.充分不必要条件
B.必要不充分条件
C.充分必要条件
D.既不充分也不必要条件
答案
当b≥0时,a2+b≥0成立.
当a=3,b=-1时,满足a2+b≥0成立,但b≥0不成立.
∴“b≥0”是“a2+b≥0”充分不必要条件.
故选:A.
已知a,b∈R,则“b≥0”是“a2+b≥0”的( )
A.充分不必要条件
B.必要不充分条件
C.充分必要条件
D.既不充分也不必要条件
当b≥0时,a2+b≥0成立.
当a=3,b=-1时,满足a2+b≥0成立,但b≥0不成立.
∴“b≥0”是“a2+b≥0”充分不必要条件.
故选:A.
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