tan∠APD的值是( B,2 ) --------------------------∠APD=∠CAP+∠ACPtan∠CAP=1/3tan∠ACP=1 tan∠APD=tan(∠CAP+∠ACP) =(tan∠CAP+tan∠ACP)/(1-tan∠CAP*tan∠ACP) =(1+1/3)/(1-1*1/3) =4/2 =2