- 問題詳情:已知⊙O是△ABC的外接圓,過點A作⊙O的切線,與CO的延長線交於點P,CP與⊙O交於點D.(Ⅰ)如圖①,若∠P=38°,求∠B的大小;(Ⅱ)如圖②,若AP∥BC,∠B=72°,求∠BAC的大小. 【回答】解:(Ⅰ)如解圖①,連接OA,∵PA與⊙O與相切,∴∠PAO=90°,∴∠POA=90°-∠P=90°-38°=52...
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- 問題詳情:如圖,AB是⊙O的直徑,AB=2,點C在⊙O上,∠CAB=30°,D為的中點,P是直徑AB上一動點,則PC+PD的最小值為( )A. B. C. D. 【回答】B知識點:圓的有關*質題型:選擇題...
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- FungaldiseasessuchasPCP,candidiasis,cryptococcosisandpenicilliosis.PCPcanbetreatedwithantibioticsand,ifyourCD4countdropsbelow200,youmaybegivenantibioticstopreventaPCPinfection.Thedechlorinationofpentachlorophenol(PCP)byanaerobicgranularsludgewasstudi...
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