椭圆范围与最值问题是平面解析几何中的重点和难点,也是历年高考考查的热点之一.这类问题常涉及夹角、长度、面积、离心率的变化情况,综合性强,计算量大,求解过程复杂,令很多人望而生畏,无从下笔.本文以三角函数为立足点,从不同的角度给出解决这类问题的五种转化策略,协助大家克服难点. Ellipse range and the value of the problem is the most important and difficult plane analytic geometry, but also over the years, one of the hot spots examining the college entrance examination. Such issues often involve changes in angle, length, area, eccentricity, comprehensive, computationally intensive , The solution process is complex, so many people dauntless, no pen .This paper takes the trigonometric function as a foothold, from different angles to provide five kinds of conversion strategies to solve such problems, to help you overcome the difficulties.