论文部分内容阅读
高中阶段求二面角是学习的难点,也是高考的重点.常见的方法有定义法、垂线法、垂面法、投影面积法等几何法,但这些方法都无一例外地涉及作辅助线,这给我们带来了很大的困难.坐标向量法在建系计算中也是难点.本人在教学三棱锥时无意发现了用向量方法推导的一个求二面角的新公式,公式具有较简洁的对称美,便于操作,条件简单,有较广泛的适用性.用这一公式来解决相应的问题,得到了一种全新的解法.
Diagenesis in high school is the difficulty of learning, but also the focus of the college entrance examination. Common methods are defined method, vertical method, vertical method, the projected area method and other geometric methods, but these methods are without exception involved in the auxiliary line , Which brings us a great deal of difficulty.Coordinate vector method is also difficult in the calculation of building system.I did not intend to find a new formula for dihedral angle deduced by vector method when teaching pyramids, Symmetrical beauty, easy to operate, simple conditions, has a wide range of applicability.Using this formula to solve the corresponding problems, has been a completely new solution.