某日,和数学组同仁一起听组内公开课。教学内容为《一元一次不等式组》,最后3分钟张老师提出一个问题:“三角形三边长分别为4,a-1,7,则a的取值范围是_________。”两分钟后有学生报出了答案,教师在黑板上简单列出不等式组后宣布下课。在评课环节,教师纷纷表示这节课教学设计合理,教学方法恰当,有效解决了教学重点和难点问 One day, we will listen to the open class together with my colleagues in mathematics. The teaching content is “one dollar inequality group”. In the last 3 minutes, Teacher Zhang raised a question: “The three sides of the triangle are 4, a-1,7, respectively, and the range of a is _________.” After two minutes Some students reported the answer, the teacher simply listed on the blackboard after the inequality group announced the get out of class. In the assessment session, teachers have said that this lesson teaching design is reasonable, appropriate teaching methods, effective solution to the teaching of the key and difficult to ask