【考情分析】存在性问题与证明问题是近几年高考试题对解析几何考查的一种热点题型,以判断满足条件的点、直线、参数是否存在,证明直线与圆锥曲线的位置关系.数量关系(等量或不等量)为主要呈现方式,多以解答题的形式考查.【复习要点】(1)圆锥曲线中的取值范围问题. 【Analysis】 Existence problems and proof of the problem in recent years, college entrance examination test analytic geometry of a hot question type to determine the conditions to meet the point, line, the existence of parameters, to prove the linear relationship between the position and the conic curve. Quantitative relationship (equal or unequal amount) as the main presentation, mostly in the form of answer questions to examine [Review points] (1) conical curve in the range of values.