AB=AC,AD⊥源悔BC,所以∠BAD=∠CAD图中OF,OE分别垂直AC,AB则 OE=OF,又OC=OP所以直角△OPE全等腊磨于直角△OCF则有∠轮裂斗POE=∠COF所以∠COP=∠EOF=60°
