如图,四棱锥P-ABCD的底面是正方形,PD⊥底面ABCD,点E在棱PB上.
(Ⅰ)求证:平面AEC⊥平面PDB;
(Ⅱ)当
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102747345864069/SYS201311031027473458640018_ST/0.png)
,且直线AE与平面PBD成角为45°时,确定点E的位置,即求出
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102747345864069/SYS201311031027473458640018_ST/1.png)
的值.
考点分析:
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