如图所示,已知AB=AC,AE=AF,BE与CF交于点D,求证:D在∠BAC的平分线上.

如图所示,已知AE垂直AB,AF垂直AC,AE=AB,AF=AC,求证.EC垂直BF 如图所示,已知ae⊥ab,af⊥ac,ae=ab,af=ac.求证ec⊥bf 如图所示,已知AE⊥AB,AF⊥AC,AE=AB,AF=AC.求证：（1）EC=BF；（2）EC⊥BF. 如图所示,已知AE⊥AB,AF⊥AC,AE=AB,AF=AC.求证①EC=BF②EC⊥BF. 如图所示,已知AE⊥AB,AF⊥AC,AE=AB,AF=AC.求证：（1）EC=BF；（2）EC⊥BF 如图所示,已知：AE垂直于AB,AF垂直于AC,AE=AB,AF=AC.求证：(1)EC=BF;如图所示,已知：AE垂直于AB,AF垂直于AC,AE=AB,AF=AC.求证：(1)EC=BF;(2)EC垂直于BF 如图所示,已知AE垂直于AB,AF垂直于AC,AFE=AB,AF=AC,是说明EC垂直于BF急急急急急急! 如图所示,已知AE垂直于AB,AF垂直于AC,AFE=AB,AF=AC,说明EC垂直于BF 如图所示,已知AB=AC,AE=AF,AE⊥Ec,AF⊥BF,垂足点为E、F求证：∠1=∠2 如图所示,已知AE⊥AB,AF⊥AC,AF=AC,求证：（1）EC=BF（2）EC⊥BF 如图所示,已知AB=AE,AC=AF,BC=EF.求证：∠FAC=∠BAE 如图所示,已知三角形ABC中,AB=AC,F在AC上,在BA的延长线上取AE=AF,求证：EF⊥BC. 已知AE=AF,AB=AC,角A=60,角B=24,求角BOE的度数? 已知如图所示,三角形ABC中,AB=AC,点E在CA的延长线上,且EF垂直BC求证AE=AF 如图所示,已知AB=AC,AE=AF,BE与CF交于点D,求证:D在∠BAC的平分线上. 如图所示,已知AB=DC,AE=DF,CE=BF试说明AF=DE 如图,已知AE⊥AD,AF⊥AB,AB//CD,AE=CD,AE=AD,AF=CD,求证AC=EF 已知AE⊥AB,AF⊥AC,AE=AB,AF=AC.试证明:(1)EC=BF;(2)EC⊥BF