函数是高中数学的主线,也是高考的考查重点,近年来函数与其它知识“交汇”的题型已越来越受到命题者青睐.下面围绕这类题型,从各地高考模拟题中选择数例,分类浅析. 1.函数与三角的“交汇”例1 设二次函数f(x)=x2十bx+c(b,c∈R),已知无论α、β为何实数,恒有f(sinα)≥0,f(2+cosβ)≤0.(1)求证b+c=-1且 Function is the main thread of high school mathematics, and it is also the focus of the college entrance examination. In recent years, the questions and the intersection of function and other knowledge have become more and more favored by the proposition. The following questions are selected from the simulated questions of the local college entrance examination. , Classification analysis. 1. The “convergence” of functions and triangles. Example 1 Let the quadratic function f(x)=x2 tens bx+c(b,c∈R) known to be constant regardless of α, β. (sinα) ≥ 0, f(2+cosβ) ≤ 0. (1) Proof b+c=-1 and