二次函数y=ax2+bx+c(a≠0)的图像与其系数的关系是中考命题的重点.这类题能考查我们的逻辑推理能力和数与形的转化能力.现以2014年的中考题为例,说明这类题的解法.典型试题例1二次函数y=ax2+bx+c(a≠0)的图像如图1所示,则下列结论中正确的是().A.c>-1 B.b>0C.2a+b≠0 D.9a+c>3b解:图像与y轴的交点在点(0,-1)的下方,∴c<-1,选项A错误; The quadratic function y = ax2 + bx + c (a ≠ 0) the relationship between the image and its coefficient is the focus of the senior high school entrance examination questions .This type of question can test our logical reasoning ability and number and shape transformation ability. Typical test example 1 quadratic function y = ax2 + bx + c (a ≠ 0) the image shown in Figure 1, then the following conclusion is correct () .Ac > -1 Bb> 0C.2a + b ≠ 0 D.9a + c> 3b Solution: The intersection of the image and the y-axis is below the point (0, -1)