基于一致性视角谈谈对余弦定理推导的认识

Talk about the Understanding of the Derivation of the Cosine Theorem from the Perspective of Consistency

摘要: 本文以学生学习发展的认知路径顺序对三角形知识进行梳理，从一致性视角，呈现了三角形各元素之间的关系和余弦定理之间的联系，同时从不同视角对余弦定理进行了证明，对三角形边角关系形成一个整体性的理解，为教师教学和学生学习余弦定理提供一定的思路。

Abstract: This article sorts out triangle knowledge in the order of students’ cognitive paths of learning and development. From a consistency perspective, it presents the relationship between the elements of the triangle and the connection between the cosine theorem. It also proves the cosine theorem from different perspectives., forming a comprehensive understanding of the relationship between the sides and angles of a triangle, and providing certain ideas for teachers to teach and students to learn the cosine theorem.