浅议空间向量在立体几何中的应用

• 作 者: 严美成
• 机 构: 湖北省江陵中学,
• 出 处: 语数外学习(高中版下旬)
• 发表日期: 2015年01期
• 关键词: 空间向量 立体几何 运算过程 二面角 选择 思维量 求解 面积 方法 等体积法 坐标法 运算量 线面角 平面角 几何题 几何法 训练 学生 射影 入口

高考中的立体几何题属于中档题,入口较宽,有一定的思维量和运算量。如何轻松准确地解决好这道大题,不影响考试的节奏和心情。方法的选择至关重要。笔者不赞同一根筋地选择几何法或坐标法。要因题制宜,多条腿走路。最短的时间,最小的运算,最简单的思维是我们在平时训练当中应该刻意培养的。如求解线面角时巧用等体积法,求解二面角时利用射影面积与原面积的比值等于二面角的

College entrance examination of the three-dimensional geometry problems are mid-range questions, wide entrance, there is a certain amount of thinking and computing. How to easily and accurately solve this major problem, does not affect the rhythm and mood examination. The choice of method is crucial. I do not agree with a choice of geometric method or coordinate method. To the appropriate conditions, walking on multiple legs. The shortest time, the smallest operation, the simplest thinking is that we should be deliberately trained in peacetime training. Such as the use of line angle when solving the use of equal volume method, solving the dihedral angle using the projective area and the original area ratio equal to the dihedral angle