1初三9-10月考:二次函数精选abc.....................................................................................................................................2与x交点...........................................................................................................................9顶点...................................................................................................................................9对称性.............................................................................................................................10增减性.............................................................................................................................11取值范围........................................................................................................................13平移.................................................................................................................................14抛物线旋转....................................................................................................................15函数与方程/不等式.......................................................................................................16解答.................................................................................................................................212abc1.在平面直角坐标系xOy中,二次函数2yaxbxc的图像如图所示,下列说法正确的是【】A.20,40abcbacB.20,40abcbacC.20,40abcbacD.20,40abcbac2.如图,在平面直角坐标系xOy中,抛物线20yaxbxca的对称轴是13x,在下列结论中,错误的是【】A.a>0B.b>0C.c>-1D.240bac3.已知函数2yxbxc,其中b>0,c<0,此函数的图象可以是【】A.B.C.D.34.在同一平面直角坐标系中,一次函数yaxb和二次函数2yaxbxc的图象可能为【】A.B.C.D.5.如图新示,在平面直角坐标系xOy中,抛物线20yaxbxca的对称轴是直线13x,则下列结论中,正确的是【】A.c<-1B.2a+3b=0C.当13x时,y的最大值为99caD.a-b+c<06.二次函数20yaxbxca的...