(2013•许昌二模)如图,已知PE切圆O于点E,割线PBA交圆O于A,B两点,∠APE的平分线和AE、BE分别交于点C
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证明:(Ⅰ)∵PE切圆O于E,∴∠PEB=∠A,

又∵PC平分∠APE,∴∠CPE=∠CPA,

∴∠PEB+∠CPE=∠A+∠CPA,

∴∠CDE=∠DCE,即CE=DE.

(Ⅱ)因为PC平分∠APE∴[CA/CE=

PA

PE],

又PE切圆O于点E,割线PBA交圆O于A,B两点,

∴PE2=PB•PA,

即[PA/PE=

PE

PB]

∴[CA/CE]=[PE/PB]