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(2003•武汉)已知:抛物线y=ax2+bx+c(a<0)经过点(-1,0),...
(2003•武汉)已知:抛物线y=ax2+bx+c(a<0)经过点(-1,0),且满足4a+2b+c>0,以下结论:①a+b>0;②a+c>0;③-a+b+c>0;④b2-2ac>5a2,其中正确的个数有( )
A.1个
B.2个
C.3个
D.4个
考点分析:
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