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二次函数y=ax2+bx+c(a≠0)的图象如图所示,其对称轴为直线x=1,有如...
二次函数y=ax
2+bx+c(a≠0)的图象如图所示,其对称轴为直线x=1,有如下结论:
①c<1;②2a+b=0;③b
2<4ac;④若方程ax
2+bx+c=0的两根为x
1,x
2,则x
1+x
2=2,
则正确的结论是( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101193752520768025/SYS201311011937525207680010_ST/images0.png)
A.①②
B.①③
C.②④
D.③④
考点分析:
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