论文部分内容阅读
三角形既可以按边分类也可以按角分类,当我们得到了它们的边(角)之间的关系或最大角的度数时,就能据此判定三角形的形状.下面向大家介绍判断三角形形状的多种方法,相信对开拓同学们的思维,提高解题技能和技巧会有一定的帮助.一、利用因式分解进行判定例1在△ABC中,∠A、∠B、∠C所对的边分别为a、b、c,a~2+2ab=c~2+2bc,试判定△ABC的形状.解析∵a~2+2ab=c~2+2bc,a~2-c~2+2ab-2bc=0,即(a-c)(a+c)+2b(a-c)=0,
Triangles can be classified by edge or by angle, and when we get the relationship between their angles or the degree of the maximum angle, we can determine the shape of the triangle. A variety of methods, I believe to develop students’ thinking, improve the skills and skills to solve problems will be some help. First, the use of factorization to determine cases 1 △ ABC, ∠A, ∠B, ∠C right Assume that the shape of ABC is determined as a, b, c, a ~ 2 + 2ab = c ~ 2 + 2bc, respectively.Analyzing ∵a ~ 2 + 2ab = c ~ 2 + 2bc and a ~ 2-c ~ 2 + 2ab-2bc = 0, ie (ac) (a + c) + 2b (ac) = 0,