立体几何的垂直问题是立几高考中两个考查方向之一.在整张高考试卷中属于中低档题,也是考生势必要抓住的题型.如何抓住重点,突破难点,有效解题,可以从以下几道例题中看出一二.题型一直线与平面垂直与直线与直线垂直的转化例1如图1,在四棱锥P-ABCD中,PA⊥底面ABCD,AB⊥AD,AC⊥CD,∠ABC=60°,PA=AB=BC,E是PC的中点. Vertical geometry of the three-dimensional geometry is one of the two test directions in the examination papers in the entire college entrance examination belongs to the middle and low questions, candidates are bound to seize the problem .How to seize the key to breaking the difficult and effective solution to problems, Can be seen from the following few examples of one or two questions type a straight line and the plane perpendicular to the straight line with a straight line transformation Example 1 In Figure 1, pyramid P-ABCD, PA⊥ bottom ABCD, AB ⊥ AD, AC ⊥ CD, ∠ ABC = 60 °, PA = AB = BC, E is the midpoint of the PC.