- 问题详情:如图示,三根长度均为L的细杆AB、AC、AD下端固定在A点.AC杆竖直.α>β,杆的端点连接有光滑金属丝BC、CD.金属丝上套有光滑小环*、乙.使小环*、乙分别从C点沿金属丝CB、CD下滑到B和D点,下滑时间分别为t*、t乙.下列正确的是( ...
- 17265
- 问题详情:如图,△ABC和△A′B′C′关于直线m对称.(1)结合图形指出对称点;(2)延长线段AC与A′C′,它们的交点与直线m有怎样的关系?其他对应线段(或其延长线)的交点呢?你发现了什么规律,请叙述出来并与同伴交流.【回答】(1)C′与C,B与B′,A与A′(2)AC与A′C′的延长线的交点在直线m上,...
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- 问题详情:如图.PA、PB是⊙O的切线.AC是⊙O的直径.∠P=50°,则∠BOC的度数为 A.50° B.25° C.40° D.60° 【回答】A知识点:点和圆、直线和圆的位置关系题型:选择题...
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- 问题详情:DoyouknowwhatschoollifeislikeinSingapore?InSingapore,aclassonlylastshalfanhour,buttherearenobreaksbetweenclasses.Thestudentsonlyhavea30-minuteteabreakafter3or4classes.Theydonotdoeyeexercises.YaoSuyusaidoureyeexerciseswereunfamiliar(不熟悉)toh...
- 24437
- HXN5High-powerACDriveDieselLocomotiveCarbodyofNXN3high-powerACdiesellocomtoveThepaperintroducesanovelmicrocomputer-basedwithnon-contacttechnicalityofthehighpowerACcompensatedstabilizer....
- 7966
- 问题详情:MoreAmericanpeopletaketheirtroubleswiththemonholiday,accordingtoanewsurvey.Although40percentsaidthatthemainreasonforgoingawayistoescapepressure(压力)fromwork,almostallsaidtheyworrymorethantheydoathome.Onlyfourinevery100saidthattheyarehappyand...
- 24573
- 问题详情:题面:如图,已知AC⊥BC,BD⊥AD,AC与BD交于O,AC=BD.求*:(1)BC=AD; (2)△OAB是等腰三角形.【回答】详解:(1)∵AC⊥BC,BD⊥AD,∴△ABC与△BAD是直角三角形,在△ABC和△BAD中,∵AC=BD,AB=BA,∠ACB=∠BDA=90°,∴△ABC≌△BAD(HL).∴BC=AD.(2)∵△ABC≌△BAD,∴∠CAB=∠DBA,∴OA=...
- 12733
- 问题详情:如图,AD⊥AE,AB⊥AC,AD=AE,AB=AC.求*:△ABD≌△ACE. 【回答】*:∵AD⊥AE,AB⊥AC,∴∠CAB=∠DAE=90°.∴∠CAB+∠CAD=∠DAE+∠CAD,即∠BAD=∠CAE.在△ABD和△ACE中,∴△ABD≌△ACE.知...
- 24701
- 问题详情:如图,AB=AC,AB⊥AC,AD⊥AE,且∠ABD=∠ACE.求*:BD=CE.【回答】*:∵AB⊥AC,AD⊥AE,∴∠BAE+∠CAE=90°,∠BAE+∠BAD=90°,∴∠CAE=∠BAD.又AB=AC,∠ABD=∠ACE,∴△ABD≌△ACE(ASA).∴BD=CE.知识点:各地中考题型:解答题...
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- 问题详情:如图,∠A=∠E,AC⊥BE,AB=EF,BE=10,CF=4,则AC=.【回答】6.【考点】全等三角形的判定与*质.【分析】由AAS*△ABC≌△EFC,得出对应边相等AC=EC,BC=CF=4,求出EC,即可得出AC的长.【解答】解:∵AC⊥BE,∴∠ACB=∠ECF=90°,在△ABC和△EFC中,,∴△ABC≌△EFC(AAS),∴AC=EC,BC=CF=4,∵EC=BE﹣BC=10﹣4...
- 17784
- 问题详情:如图,在△ABC中,AC=BC,∠ACB=90°,AE平分∠BAC交BC于E,BD⊥AE于D,DF⊥AC交AC的延长线于F,连接CD,给出四个结论:①∠ADC=45°;②BD=AE;③AC+CE=AB;④AB﹣BC=2FC;其中正确的结论有( )A.1个 B.2个 C.3个 D.4个【回答】D【考点】全等三角形的判定与*质;角平分线的*质;等腰直角...
- 6072
- Two-waypowersupplyletsyouuseeitherbatteriesorACadaptor(soldseparately).ConsumablessuchasACadaptorarecoveredforupto3monthsfromthedateofpurchase....
- 32854
- 问题详情:OneOctobermorning,Igotofftheall-nighttraininMandalay,acityinMyanmar.Aroughmancameupandofferedtoshowmearound.ThepriceheaskedwaslessthanIwouldpayforabarofchocolateathome.SoIclimbedintohistrishaw(三轮车).Ashewasshowingmearound,hetoldmehowhehadco...
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- 问题详情:如图,在△ABC中,AB=AC,AC的垂直平分线分别交BC、AC于点D、E. (1)若AC=12,BC=15,求△ABD的周长;(2)若∠B=20°,求∠BAD的度数. 【回答】知识点:画轴对称图形题型:解答题...
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- 问题详情:已知:AB=AC,且AB⊥AC,D在BC上,求*:.【回答】*见解析【分析】作AE⊥BC于E,由于∠BAC=90°,AB=AC,得到△BAC是等腰直角三角形,再由等腰直角三角形的*质得到BE=AE=EC,进而得到BD=AE-DE,DC=AE+DE,代入BD2+CD2计算,结合勾股定理,即可得到结论.【详解】作AE⊥BC于E,如图所示.∵AB=AC,且AB⊥...
- 5798
- 问题详情:已知:如图,四边形ABCD的对角线AC,BD交于点O,BE⊥AC于E,DF⊥AC于F,点O既是AC的中点,又是EF的中点.(1)求*:△BOE≌△DOF.(2)若OA=BD,则四边形ABCD是什么特殊四边形?说明理由.【回答】【解析】(1)∵BE⊥AC,DF⊥AC,∴∠BEO=∠DFO=90°.又∵∠EOB=∠FOD,OE=OF,∴△BOE...
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- FouriertransformACvoltammetrysiliconcontrolledvoltagestabilizedAClightadjusterAC,DCorAirmotorpoweroptions.ResearchonSinglePhaseAC/ACOnvertersBasedonSimpleTopologies;ThevariablefrequencyACcontrollermountsdirectlyontheACmotor.TheACoutletishousedinrobus...
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- 问题详情:如图,D、E分别是AB、AC的中点,CD⊥AB于D,BE⊥AC于E,求*:AC=AB.【回答】【考点】轴对称的*质;全等三角形的判定.【专题】*题.【分析】作辅助线:连接BC,由CD垂直于AB,且D为AB中点,即CD所在直线为AB的垂直平分线,根据线段垂直平分线上的点到线段两端点的距离相等,得到AC=BC,又E为AC...
- 8282
- 1、90-wattACadapterandpowercord2、"RechangethebatteryorplugtheACadapteroutputintotheACadapter3、PlugtheACadapterinandprintagain.4、ThebalanceispoweredbyanACadapter.5、PlugintheACadapterandrestartyournotebook.6、Whenusingthepowercable,insertthepowerc...
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- 1、AutomaticexchangeforDCandACsupply.2、DisconnecttheACsupplyleadplugfromtheACoutletwhentheunitinnotituseforextendedperiods.3、RemovetheACsupplyleadbeforeservicingorcleaningheads,rolleretc.4、InsertingtheACsupplyleadintotheunitautomaticallydisconnect...
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- 问题详情:TheaverageFacebookuserintheUnitedStateshas245friends,accordingtoastudy________inFebruary.A.publishing B.publishedC.publish D.topublish【回答】B知识点:非谓语动词题型:选择题...
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- UsingACcontactorformotor’sphasebreakprotectionisimproperInsideisinstalledACcontactor,thermalreplay,self-settableconversionswitch.FuzzyComprehensiveEvaluationandControlofBestClosingMakingAngleofRotationalACcontactorTheutilitymodelbelongstoasilencinga...
- 26748
- 问题详情:已知点B在直线AC上,AB=8cm,AC=18cm,p、Q分别是AB、AC的中点,则PQ=____.【回答】5cm或9cm.知识点:直*、*线、线段题型:填空题...
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- 问题详情:已知:如图,DE⊥AC,BF⊥AC,AD=BC,DE=BF,.求*:AB∥DC【回答】.∵DE⊥AC,BF⊥AC,∴∠AED=∠CFB=90°∠AFB=∠CED=90°…………1分在Rt△ADE和Rt△BCF中∴Rt△ADE≌Rt△BCF(HL)…………3分∴AE=CF…………4分∴AE+EF=CF+EF 即AF=CE…………5分在△AFB和△CED中…………7分...
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- 1、AC/DCandDC/ACConvertyCircuitsinPowerSupplyEquipment;2、StudyonDoubly-fedInductionGenerationSystemwithAC/DC/ACExcitationConverter;3、ElectroMagneticCompatibilityDesignofAC/DC/ACConverterUsedinWindPowerGenerator;4、ResearchontheDC/ACInverterSupplies...
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