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如图,在菱形ABCD中,点E在边AD上,BE⊥AD,∠BCE=30°,若AE=2,则边BC的长为( )
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如图在▱ABCD中BC=2AB=4点E.F.分别是BCAD的中点.1求证△ABE≌△CDF2当四边形
如图在△ABC中点D.是边BC上的点与B.C.两点不重合过点D.作DE∥ACDF∥AB分别交ABAC
若AD⊥BC,则四边形AEDF是矩形
若AD垂直平分BC,则四边形AEDF是矩形
若BD=CD,则四边形AEDF是菱形
若AD平分∠BAC,则四边形AEDF是菱形
如图在梯形ABCD中AD∥BCE.为BC的中点BC=2ADEA=ED=2AC与ED相交于点F.1求证
如图在直角梯形ABCD中AD∥BCAB⊥ADBC=CDBE⊥CD垂足为E.点F.在BD上连接AFEF
已知如图在四边形ABCD中AD∥BC∠BDC=∠BCD点E.是线段BD上一点且BE=AD.证明△AD
如图已知四边形ABCD是菱形点M.N.分别在ABAD上且BM=DNMG∥ADNF∥AB点F.G.分别
如图已知点E.F.分别是▱ABCD的边BCAD上的中点且∠BAC=90°.1求证四边形AECF是菱形
如图已知E.F.分别是□ABCD的边BCAD上的点且BE=DF.1求证四边形AECF是平行四边形2若
如图在梯形纸片ABCD中AD∥BCAD>CD将纸片沿过点D.的直线折叠使点C.落在AD上的点C.′处
1如图已知在△AFD和△CEB中点A.E.F.C.在同一直线上AE=CF∠B.=∠D.AD∥BC.求
如图在四边形ABCD中AD∥BC点E.在BC的延长线上CE=BC连接AE交CD边于点F.且CF=DF
如图四边形ABCD是菱形点M.N.分别在ABAD上且BM=DNMG∥ADNF∥AB点F.G.分别在B
如图已知点E.F.分别是□ABCD的边BCAD上的中点且∠BAC=90°.1求证四边形AECF是菱形
如图9等腰梯形ABCD中AD∥BC点E.是线段AD上的一个动点E与A.D.不重合G.F.H.分别是B
如图在△ABC中点D.是边BC上的点与B.C.两点不重合过点D.作DE∥ACDF∥AB分别交ABAC
若AD⊥BC,则四边形AEDF是矩形
若BD=CD,则四边形AEDF是菱形
若AD垂直平分BC,则四边形AEDF是矩形
若AD平分∠BAC,则四边形AEDF是菱形
如图在矩形ABCD中AB=8BC=10E.是AB上一点将矩形ABCD沿CE折叠后点B.落在AD边的点
已知如图四边形ABCD中AD∥BCAD=CDE.是对角线BD上一点且EA=EC.1求证四边形ABCD
如图在四边形ABCD中AD∥BCAD≠BC∠B.=90°AG∥CD交BC于点G.点E.F.分别为AG
如图在每一个四边形ABCD中均有AD∥BCCD⊥BC∠ABC=60°AD=8BC=12.1如图①点M
如图等腰梯形ABCD中AD∥BC点E.是线段AD上的一个动点E与A.D.不重合G.F.H.分别是BE
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WhenOliverSacks82diedonAug30athishomeinNewYorkCitytheworldwassaddenedbythelossofabrilliantneurologist神经学者andatrulybeautifulmind. London﹣bornSackswasmostfamousforhiswriting.AForbesobituary讣告callshimoneofthegreatestwritersofscienceofthepast50years.Maybethegreatest. Inhisbest﹣selling1985bookTheManWhoMistookHisWifeforaHatSacksdescribedamanwhocouldnottellthedifferencebetweenhiswife'sfaceandhishatbecausehisbrainhaddifficultytellingwhathesaw. In2006Discovermagazinerankeditamongthe25greatestsciencebooksofalltimedeclaringLotsofneuroscientistsnowlookingintothemysteriesofthehumanbraincite列举thisbookastheirgreatestinspiration/ His1973bookAwakeningsisaboutagroupofpatientswhowerefrozeninadecades﹣longsleepuntilSackstriedanewtreatment.Thebookledtoa1990movieinwhichSackswasactedbyRobinWilliams.Itwasnominated提名forthreeAcademyAwards. AnotherbookAnAnthropologistonMarspublishedin1995describedcaseslikethatofapainterwholosthiscolorvisioninacaraccidentbutfoundnewcreativepowerinblack﹣and﹣whiteimages.Sacksalsowrotethestoryofa50﹣year﹣oldmanwhosuddenlyregainedsightafternearlyalifetimeofblindness.Theexperiencewasadisaster.Theman'sbraincouldnotmakesenseofthevisualworld.Afterafullandrichlifeasablindpersonhebecameaverydisabledandmiserable悲惨的sightedmanSackswrote.Whenhewentblindagainhewasrathergladofit. DespitethedramaandunusualstoriesSacks'bookswerenotmeanttobefreakshows.OliverSackshumanizesillness…hewritesofbodyandmindandfromeveryoneofhiscasestudiesthereshowsafeelingofrespectforthepatientandfortheillnessRoaldHoffmannaNobelPrize﹣winningchemistsaidin2001. WhenSacksreceivedtheLewisThomasPrizeforsciencewritingin2002thecitation荣誉状declareduSackspressesustofollowhimintounknownareasofhumanexperienceandforcesustorealizeoncetherethatwearefacingonlyourselves. 1ThefollowingstatementsarewrongEXCEPT. A.TheManWhoMistookHisWifeforaHatwasrankedamongthe25greatestsciencebooks B.AnthropologistonMarsledtoamovieinwhichSackswasactedbyRobinWilliams C.Sacksrecordedamanwhoregainedsightafteralifetimeblindness D.Awakeningsisoftencitedbyneuroscientiststoprovethemysteryofhumanbrain 2WhywasSackscalledoneofthegreatestwritersofscienceoverthepast50years? A.HewasborninLondonandmostfamousforhiswriting. B.Hewroteaseriesofbookstheinfluenceofwhichwasgreat. C.Hewasabrilliantneurologistandhadatrulybeautifulmind. D.HereceivedtheLewisThomasPrizeforsciencewritingin2002. 3Whichofthefollowingistrueaccordingtothepassage? A.OliverSackslosthiscolorvisioninacaraccident. B.OliverSackswontheNobelPrizein2002. C.Awakeningswasfilmedin1973inwhichRobinWilliamsactedasSacks. D.OliverSacksshowedrespectforhumanityinhisbooks. 4Thepassageismainlyabout. A.theawardsOliverSacks'won B.thelifeexperiencesofOliverSacks C.theinfluenceofOliverSacks'works D.thereasonswhyOliverSackssucceeded
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