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高考对双曲线问题的考查多集中于选择与填空题,所以其高考中的热点问题也就多体现为:由定义求双曲线方程、求离心率及离心率的取值范围等.热点问题1:求双曲线离心率的取值范围例1双曲线x~2/a~2-y~2/b~2=1(a>1,b>0)的焦距为2c,直线l过点(a,0)和(0,b),且点(1,0)到直线l的距离与点(-1,0)到直线l的距离之和s≥4/5c.求双曲线的离心率e的取值范围.
College entrance examinations of hyperbolic problems and more focused on the choice and fill in the blank, so the entrance examination of the hot issues will also be reflected as follows: by the definition of hyperbolic equations, seeking eccentricity and eccentricity range of values, etc. Hot issues 1 : Find hyperbolic eccentricity in the range of Example 1 hyperbolic 2 ~ 2 / a ~ 2 ~ y ~ 2 / b ~ 2 = 1 (a> 1, b> 0) the focal length of 2c, a, 0) and (0, b), and the sum of the distance from point (1,0) to line l and the distance from point (-1,0) to line l s ≥ 4 / 5c. The range of e.