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H)'67")8K(KQTpFQG;%& '%Q)Q%- %&7"K7"d. 49?KQ"d'<"L$"M "*!7_ ;4@AB!"*!)K"BKqR =4FBGH )8KQ"+-.(5-5'<""' D.9DK5%&'%"*!-. >4012"'445C9D=KH ?4!"*!)K_9K)'67")8B E4B"+KQ(,,5"+-.(/)5B"+/(C9D5 %&'%(%&!$"5C =eF-tR.)1;"$'%),/%-. 49:,/ ;4F"^&%&'%()(,)/"+!'YZ(K) Q9$"9$"K,Q/<%&Z" =49KQ)'67")8 >4KQ"+-.(l)J)"+(B9lJ%& '%"*!-.)7"B/:7"B, = Tp%&'%("+%&'%()YZ(K )Q 49$"9$"KQ<%&)KQ:R ; ;49%&'%"*!KQ =4@A/)3YZ'"*!)Q9! $"/3)'6 >43"+K(,,/"+(l)"+/3(J9 / ; :,3)['!'"*!lJ ?4\H['!)'67")8Q"+,(I9, '"*!KI [...]... 1/Chứng minh : Tứ giác AOED nội tiếp được và AC2=BC.DC 2/Gọi P là trực tâm cua tam giác ADE Chứng tỏ : Tứ giác APEO là hình thoi 3/CH cắt AE tại I Chứng tỏ : 3 điểm P,O,I thẳng hàng 4/BI cắt OC tại S Chứng minh : AS vuông góc với OH Bài 69 : Cho đường tròn tâm (O), đường kính AB Trên đường tròn lấy 1 điểm C sao cho BC>AC Các tiếp tuyến tại A và C của (O) cắt... 5/Chứng minh : IC vuông góc với MN 6/Gọi J là điểm đối xứng H qua B ,MN cắt OA tại Q và cắt BC tại L Chứng minh : đường tròn ngoại tiếp tam giác IJQ đi qua trung điểm của HL Bài 39 : Cho tam giác ABC có 3 góc nhọn nội tiếp đường tròn (O) có AB . ! 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