在数学教学中,师生往往喜欢用口诀.口诀很少写进教科书,但它功大于过,在教学中被众人相传经久不衰.下面就口诀及使用谈几点看法.一、口决的性质(1)易记诵性.“少则得,多则惑”,少就容易记,记得住才能用得上.口诀正是以字少押韵易记诵为特点的简单语句.“奇变偶不变,符号看象限”,仅十个字却概括了三角函数的54个诱导公式,言简意赅,合辙押韵.有的口诀与图象并用,事半功倍,易记性就更显著. In mathematics teaching, teachers and students often like to use oral medicine. The oral formula is rarely written in textbooks, but it is more powerful than it has been. It is passed down by people in teaching and is enduring. Here are a few points of view on how to use it and how to use it. The nature (1) is easy to remember. “When there are few, many are confused”, less is easy to remember, and you can only use it if you remember. The word of mouth is a simple sentence that is characterized by less rhyme and easy to remember. Change, sign to see the quadrant, only ten words but summed up the 54 induced formulas of the trigonometric function, concise and concise, combined rhyme. Some oral and image use, more effective, more memorable.