Teaching design of the theorem for interior angle sum of a triangle based on"four understandings"
This paper advances a teaching design of the theorem for interior angle sum of a triangle based on"four under-standings".Experimental operation:"intuitive understanding"for acquiring a perceptual understanding and savoring the mathe-matics abstractness;Theorem proving:"deep understanding"for guiding students to explore the interior angle sum theorem of a triangle and understand the rationalist spirit of mathematics;Reflective proof:"reflective understanding"for inspecting and an-alyzing different approaches to prove triangle interior angle sum theorem and understanding of the essence of different methods;Historical review:"cultural understanding"for reviewing the process of theorem discovery and recreation,appreciating mathe-matical culture.
four understandingsthe sum of the interior angles of a triangleteaching design