解三角形应用举例（Example of solving triangle）.doc

解三角形应用举例（Example of solving triangle） Example of solving triangle The fourth period (1) teaching objective (a) knowledge and skills: can use sine law, cosine theorem and other knowledge and methods to further solve the triangle problem, grasp the triangle area formula of simple derivation and Application (b) process and method: this section complements the new triangle area formula, skillfully sets doubt, guides students to prove, and summarizes the characteristics of the formula, step by step, specific for the relevant types of questions. In this lesson the proof embodies in front of knowledge vivid use, teachers should let students explore characteristics, make students grasp the sine theorem and cosine theorem in the specific argument can not sticking to formalities, several solutions to one problem. As long as students grasp the characteristics of the two theorem, they can quickly open their minds and further break through the difficulties,. (c) emotion and value: to enable students to further consolidate the knowledge, deepening the study of theorem understanding, improve the innovation ability of students; further research and discovery ability, let students experience the pleasure success in inquiry (2) teaching emphases and teaching difficulties; Teaching emphasis: deducing the formula of triangle area and solving simple related questions Teaching difficulties: the use of sine theorem, cosine theorem to prove a simple proof (3) learning methods and teaching aids The application of sine and cosine theorem, in addition to remember the correct formula, in the use of flexibility, experience formula, deformation skills, as well as the formula of conventional deformation direction, and further introduced a new triangle area formula. At the same time, we must pay attention to discuss the topic of the triangle, discuss whether the final solution conforms to the law, prevent the solution or increase the solution, and form the habit of inspection. Right angle plate, o