新版高中数学第一册 (下 )在推导二倍角的正弦、余弦、正切公式时意味深长地指出 :“……我们让同学们自己填写公式 ,是为了使大家学会怎样去发现数学规律 ,并体会化归 (这里指将一般化归为特殊 )这一基本数学思想在发现中所起的作用” .象这样的指导语教材中是少见的 ,因此它 The first edition of the new high school mathematics book (bottom), when deriving the sine, cosine, and tangent formulas of the double-angled angle, clearly pointed out: "... we let the students fill in the formulas themselves, in order to make everyone learn how to find the laws of mathematics, and realize that The role of the basic mathematics thoughts of transformation (herein referred to as generalization as special) in discovery is rare. Such instructional texts are rare and therefore