①②③④⑤ B. ①②③⑤ C.①②③ D. ①②⑤A DP EG HM BC F第7题 相关知识点: 试题来源: 解析 B 反馈 收藏
∴DG=ED-EG=(4√5)/5a . GH=AH-AG=(4√5)/(15)a . ∵∠BITF=∠DHG BHF =∠DHG, ∴在Rt△DGH中, tan∠BHF=tan∠DHG= (DG)/(GH)=3 .错.设AF与BM 交于点K.由 题得 △AEP\backsim△ABM ∴(EP)/(BM)=(AE)/(AB) 即P AB=BM⋅AE .△BFH ⊙△DAH . ∴(BF)/(DA)= (BH...
∴△AGE\backsim△ABF∴(AE)/(AF) (EG)/(FB)=(AG)/(AB)=a/(√5a)-(√5)/5⋅ ∴EG=(√5)/5BF=(√5)/5a AG=(√5)/5AB=(2√5)/5a . ∴DG-ED-EG=(1√5)/5a . GH=NH-AG=(1√5)/(15)a . ∵∠BITF=∠DHG BHF =∠DHG. ∴在 R_1△I(jH 中,tan∠BHF =tan∠DHG ...