Teaching Research On Adding Auxiliary Lines In Junior Middle School Plane Geometry

Auxiliary line is an indispensable part in teaching of geometry,and it is effective in solving geometric problems.Adding auxiliary line properly is also helpful in solving geometric problems.Based on relevant theories from both domestic and international academic documents on logic reasoning and geometrical intuition,naturalization and Piaget's theory of cognitive development,and based on literature review,questionnaire and survey,this thesis aims to talk about the function of auxiliary line in junior high school.With analyzing auxiliary line and its significance in plane geometry,the thesis will improve students' ability to solve geometry problems and their ability in making auxiliary line in geometry.With extensive analysis and data collected in students' class,this thesis hopes to help students to diminish difficulties in applying theories of plane geometry and in making auxiliary lines.It has been concluded that some teachers don't pay attention to classification of auxiliary lines in plane geometry and summary of auxiliary lines in logic reasoning in plane geometry.Teachers should be competent in using auxiliary lines and therefore help student to apply auxiliary lines in regulated ways to meet standards of teaching of geometry.Based on surveys,it is found that students find it difficult to find rationales for solutions,to differentiate basic geometric figures from complex figures,and to find basic figures correctly.And it is also found that some teachers are not able to classify auxiliary lines,and there are no proper teaching and drills on using auxiliary lines.Some teachers lack sufficient knowledge and always ignore extending knowledge in auxiliary lines by focusing only on finishing on-class tasks.To put it in a nutshell,the following suggestions are given: both teachers and students should be familiar with classification of drawing methods of auxiliary lines;teachers should include content of auxiliary lines in their teaching properly;they should offer chances for students to explore learning and summarize ways of adding auxiliary lines by students themselves;they should apply multimedia in teaching and raised students' awareness of importance of auxiliary lines and encourage them to use auxiliary lines.