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“a=2”是“直线ax+2y=0平行于直线x+y=1”的( ) A.充分而不必要...
“a=2”是“直线ax+2y=0平行于直线x+y=1”的( )
A.充分而不必要条件
B.必要而不充分条件
C.充分必要条件
D.既不充分也不必要条件
考点分析:
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B.[1,+∞)
C.(-∞,1)
D.[0,+∞)
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已知数列{a
n}满足a
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(理)已知函数
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已知
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OP•k
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(文)设函数
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2恒成立的概率.
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