探求以空间图形为背景的轨迹问题 ,要善于把立体几何问题转化到平面上 ,再联合运用平面几何、立体几何、空间向量、解析几何等知识去求解 ,实现从立体几何到解析几何的过渡 .下面通过典型例题的分析解答 ,探索题型规律 ,揭示解题方法 .例 1　己知平面α∥平面 β ,直线l α ,平 To explore the trajectory problem with spatial graphics as the background, we must be good at transforming the three-dimensional geometric problems into planes, and then use the knowledge of plane geometry, solid geometry, space vectors, analytical geometry, etc. to solve the problem, and realize the transition from solid geometry to analytic geometry. The following examples of analytical solutions to solve problem-type laws, reveal problem solving methods. Example 1 Known plane α ∥ plane β, linear l α, flat