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设函数f(x)=ax2+b(lnx﹣x),已知曲线y=f(x)在点(1,f(1))处的切线与直线x﹣y+1=0垂直. (1)求a的值; (2)求函数f(x)的极值点.
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高三上学期数学《》真题及答案
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假定英语课上老师要求同桌之间交换修改作文请你修改你同桌写的以下作文.文中共有10处语言错误每句中最多有两处.每处错误仅涉及一个单词的增加删除或修改. 增加在缺词处加一个漏字符号Λ并在其下面写出该加的词. 删除把多余的词用斜线﹨划掉. 删除在错的词下划一横线并在该词下面写出修改后的词. 注意1.每处错误及其修改均仅限一词 2.只允许修改10处多者从第11处起不计分. Thesummerholidayiscoming.MyclassmatesandIaretalkingabouthowtododuringtheholiday.Wecanchosebetweenstayingathomeandtakeatrip.Ifwestayathomeitiscomfortablebutthereisnoneedtospendmoney.Butinthatcasewewilllearnlittleaboutworld.Ifwegoonatripabroadwecanbroadenyouviewandgainknowledgeswecannotgetfrombooks.Someclassmatessuggestwecangotoplacesofinterestnearby.Ithoughtthatitisagoodidea.Itdoesnotcostmanyyetwecanstilllearnalot.
6分Gettingsickoverseascanbescary.You'reinanunfamiliarplaceandoftendon'tspeakthelanguage.Althougheachtripisdifferentthereareuniversalthingsyoucandotokeepsafe. Beprepared.Scheduleavisitwithadoctorwhospecializesintravelortheareayou'revisitingatleastfourweeksbeforeyourdeparturesaysWHOpublichealthexpertDr.GillesPoumerol.Atraveldoctorwillbeabletogiveyoutherequiredandrecommendedvaccinationsaswellasdiscussanymedicalissuesyoumaycomeacrossabroad. Getinsurance.InmanycountrieswhereyouhavelimitedaccesstohealthcaregoodhealthcareisonlyfoundintheprivatesectorandcanbeveryexpensiveDr.Poumerolsays.PlusinanemergencyreturningtotheUnitedStatescancostmorethan﹩50000.Askyourhealthinsurancecompanywhetheryourpolicyappliesoverseasandwhetheritwillcovertripstoaforeignhospital.Ifnottherearemanycompaniesthatoffershort﹣termtravelhealthinsuranceforareasonablefee.AlistcanbefoundontheUSStateDepartment'stravelwebsite. Packwell.Dr.PoumerolalsosuggestsbringinganotefromyourdoctorinEnglishandthelanguageofthecountryyou'revisiting.Packinganemergencycontactlistisimportant.Contactsshouldincludethelocalembassyrelativeswhoshouldbeinformedifyougetsickandyourhealthinsurancecompany. Beaware.Youhavetobeinchargeofyourhealth.Ifyou'rebeingtreatedabroadquestionthemedicalstaffabouttheirsterilization杀菌practicesinjectionequipmentshouldbeputinboilingwaterforatleast30minutesorusedonlyonce.Alsobesurethatdoctorsandnursesarewearingglovestopreventfluidtransfer.Limitingyouralcoholintakewillkeepyoufocusedonyoursafety.Ifyourcommonsenseisperfecttherestofyourbodyshouldfollow. 21.WhichofthefollowingisTRUEaccordingtothepassage? A.Youmustreceivesomevaccinationsaftergoingabroad. B.Alcoholintakewillkeepyoufocusedonyoursafety. C.Youshouldemployatraveldoctorwhotravelswithyou. D.It'saterriblethingtogetsickinastrangecountry. 22.AccordingtothepassageyoucanvisittheUSStateDepartment'stravelwebsitetofind. A.whichcompaniesoffershort﹣termtravelhealthinsurance B.howtogetbacktotheUnitedStateswhenyouill C.whetheryourpolicyappliesoverseasornot D.goodhealthcarewhichcovertrips 23.Whatisthebesttitleforthispassage? A.HowtoGetInsuranceAbroad B.TipsforKeepingSafeOverseas C.GetReadyforYourTrip D.AvoidDangerousTravels.
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AnewcollectionofphotosbringsanunsuccessfulAntarcticvoyagebacktolife.FrankHurley'spictureswouldbeoutstanding﹣﹣﹣﹣undoubtedlyfirst﹣ratephoto﹣journalism﹣﹣﹣iftheyhadbeenmadelastweek.Infacttheywereshotfrom1914through1916mostofthemafteradisastrousshipwreck海难byacameramanwhohadnoreasonableexpectationofsurvival.Manyoftheimageswerestoredinanicechestunderfreezingwaterinthedamagedwoodenship.TheshipwastheEnduranceasmalltightNorwegian﹣builtthree﹣masterthatwasintendedtotakeSirErnestShackletonandasmallcrewofseamenandscientists27meninalltothesouthernmostshoreofAntarctica'sWeddellSea.FromthatpointShackletonwantedtoforceapassagebydogsled雪橇acrossthecontinent.ThejourneywasintendedtoachievemorethanwhatCaptainRobertFalconScotthaddone.CaptainScotthadreachedtheSouthPoleearlyin1912buthaddiedwithhisfourcompanionsonthemarchback.AswriterCarolineAlexandermakesclearinherforcefulandwell﹣researchedstoryTheEnduranceadventuringwaseventhenathoroughlycommercialeffort.Scott'slastjourneycompletedasbelayinatentdyingofcoldandhungercaughttheworld'simaginationandafilmmadeinhishonordrewcrowds.ShackletonaonetimeBritishmerchant﹣navyofficerwhohadgottowithin100milesoftheSouthPolein1908startedabusinessbeforehis1914voyagetomakemoneyfrommovieandstillphotography.FrankHurleyaconfidentandgiftedAustralianphotographerwhoknewtheAntarcticwashiredtomaketheimagesmostofwhichhaveneverbeforebeenpublished.33.WhatdoweknowaboutthephotostakenbyHurley?A.TheyweremadelastweekB.TheyshowedunderseasceneriesC.TheywerefoundbyacameramanD.Theyrecordedadisastrousadventure34.WhoreachedtheSouthPolefirstaccordingtothetext?A.FrankHurleyB.ErnestShackletonC.RobertFalconScottD.CarolineAlexander35.WhatdoesAlexanderthinkwasthepurposeofthe1914voyage?A.ArtisticcreationB.ScientificresearchC.MoneymakingD.Treasurehunting.
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8分DianaJacobsthoughtherfamilyhadaworkableplantopayforcollegeforher21﹣year﹣oldtwinsonsacombinationofsavingsincomescholarshipsandamodestamountofborrowing.Thenherhusbandlosthisjobandtheplanfellapart. IhavetwokidsincollegeandIwanttosay'comehome'butatthesametimeIwanttoprovidethemwithagoodeducationsaysJacobs. TheJacobsfamilydidworkoutasolutionTheyaskedandreceivedmoreaidfromtheschoolsandeachsonincreasedhisborrowingtothemaximumamountthroughthefederalloan贷款program.Theywilleachgraduatewith﹩20000ofdebtbutatleasttheywillbeabletofinishschool. WithunemploymentrisingfinancialaidadministratorsexpecttohearmorefamiliesliketheJacobs.Morestudentsareapplyingforaidandmorefamiliesexpecttoneedstudentloans.Collegeadministratorsareconcernedthattheywillnothaveenoughaidmoneytogoaround. Atthesametimetuition学费continuestorise.AreportfromtheNationalCenterforPublicPolicyandHigherEducationfoundthatcollegetuitionandfeesincreased439%from1982to2007whileaveragefamilyincomerosejust147%.Studentborrowinghasmorethandoubledinthelastdecade Ifwegoonthiswayforanother25yearswewon'thaveanaffordablesystemofhighereducationsaysPatrickM.Callanpresidentofthecenter.Themiddleclassfamilieshavebeenfinancingitthroughdebt.Theywillsendkidstocollegewhateverittakesevenifthatmeansahugeamountofdebt. Financialaidadministratorshavebeenhavingahardtimeasmanycompaniesdecidethatstudentloansarenotprofitableenoughandhavestoppedmakingthem.Thegoodnewshoweveristhatfederalloansaccountforaboutthreequartersofstudentborrowingandthegovernmentsaysthatmoneywillflowuninterrupted. 28.HowdidtheJacobsmanagetosolvetheirproblem? A.Theyaskedtheirkidstocomehome. B.Theyborrowed$20000fromtheschool. C.Theyencouragedtheirtwinsonstodopart﹣timejobs. D.Theygothelpfromtheschoolandthefederalgovernment. 29.Financialaidadministratorsbelievethat. A.morefamilieswillfacethesameproblemastheJacobsfamily B.thegovernmentwillreceivemorelettersofcomplaint C.collegetuitionfeeswilldoublesoon D.America'sunemploymentwillfall 30.Whatcanwelearnaboutthemiddleclassfamiliesfromthetext? A.Theyblamedthegovernmentforthetuitionincrease. B.Theirincomeremainedsteadyinthelastdecade. C.Theywilltrytheirbesttosendkidstocollege. D.Theirdebtswillbepaidoffwithin25years. 31.Accordingtothelastparagraphthegovernmentwill. A.providemoststudentswithscholarships B.dismisssomefinancialaidadministrators C.stopthecompaniesfrommakingstudentloans D.goonprovidingfinancialsupportforcollegestudents.
15分Asfoodistothebodysoislearningtothemind.Westrengthenourbodies66takinginadequatenutritiousfood.Likewiseweshouldkeeplearningdaybydaytoexpandourintellectualcapacity.67isconstantlearningthatsuppliesuswithlargeamountsofenergytosharpenourpowerofreasoning68analyzeandjudgment.Moreovercontinuouslearningis69ittakestokeeppacewiththetimesintheInformationAge. Schooliswherewe70teachbutitisbynomeanstheonlyworkshopfortheacquisitionofknowledge.Onthecontrarylearningshouldbe71never﹣endingprocessfromthecradletothegrave.Ina72rapidchangingworldtostoplearningforjustafewdayswillmakeapersonlagbehind.What'sworsetheanimalnature73hidedeepinourmindwillcometolife74canweakenourdeterminationtoachievesuccess.Thereforetostaymentallyyoungwehavetotakelearning75alifelongcareer.
合理利用和转化NO2SO2CONO等污染性气体是环保领域的重要课题. 1用CH4催化还原氮氧化物可以消除氮氧化物污染.已知 ①CH4g+4NO2g═4NOg+CO2g+2H2Og△H=﹣574.0kJ/mol ②CH4g+4NOg═2N2g+CO2g+2H2Og△H=﹣1160.0kJ/mol ③H2Og=H2O1△H=﹣44.0kJ/mol CH4g与NO2g反应生成N2gCO2g和H2Ol的热化学方程式是. 2.已知2NOg+O2g⇌2NO2g的反应历程分两步 ①2NOg⇌N2O2g快v1正=k1正•c2NOv1逆=k1逆•cN2O2 ②N2O2g+O2g⇌2NO2g慢v2正=k2正•cN2O2•cO2v2逆=k2逆•c2NO2 一定温度下反应2NOg+O2g⇌2NO2g达到平衡状态该反应的平衡常数的表达式K=用k1正k1正k2逆k2逆表示反应①的活化能E1与反应②的活化能E2的大小关系为E1E2填“>”“<”或“=” 3用活性炭还原法处理氮氧化物的有关反应为Cs+2NOg⇌N2g+CO2g. 向恒容密闭容器中加入一定量的活性炭和NO恒温T℃时各物质的浓度随时间的变化如下表 ①T℃时该反应的平衡常数为保留两位有效数字 ②在31min时若只改变某一条件使平衡发生移动40min50min时各物质的浓度如上表所示则改变的条件是. ③在51min时保持温度和容器体积不变再充入NO和N2使二者的浓度均增加至原来的两倍则化学平衡填“正向移动”“逆向移动”或“不移动”. 4反应N2O4g⇌2NO2g△H>0在一定条件下N2O4与NO2的消耗速率与各自的分压分压=总压×物质的量分数有如下关系vN2O2=k1•pN2O4vNO2=k2•p2NO2其中k1k2是与温度有关的常数相应的速率与N2O4或NO2的分压关系如图所示. 在T℃时图中MN点能表示该反应达到平衡状态理由是.改变温度vNO2会由M点变为AB或CvN2O4会由N点变为DE或F当升高到某一温度时反应重新达到平衡相应的点分别为填字母.
如图所示两端开口粗细均匀的足够长玻璃管插在大水银槽中管的上部有一定长度的水银柱两段空气柱被封闭在左右两侧的竖直管中.开启上部连通左右水银的阀门A当两侧气体温度为390K稳定时水银柱的位置如图所示其中左侧空气柱长度L1=45cm左右两侧顶部的水银面的高度差为h1=7cm左侧空气柱底部的水银面与水银槽面高度差为h2=3cm大气压强为75cmHg.求 ①右管内气柱的长度L2 ②关闭阀门A当两侧气体温度升至570K时左侧竖直管内气柱的长度L3.槽内水银面高度大气压强视为不变
小明同学通过实验探究某一金属电阻的阻值R随温度t的变化关系已知该金属电阻在常温下的阻值约10ΩR随t的升高面增大实验电路如图1所示控温箱用以调节金属电阻的温值. 实验时闭合S.先将开关K与1端闭合调节金属电阻的温度分别记下温度t1t2…电流表的相应示数I1I2…然后将开关K与2端闭合调节电阻箱使电流表的实数再次为I1I2…分别记下电阻箱相应的示数R1R2… 1有以下两电流表实验电路中应选用 A.量程0﹣100mA内阻约2ΩB.量程0~0.6A内阻可忽略 2实验过程中要将电阻箱的阻值由9.9Ω调节至10.0Ω.需旋转图3中电阻箱的旋钮“a““b”“c”正确的操作顺序是 ①将旋钮a由“0”旋转至“1 ②将旋钮b由9°旋转至“0” ③将旋钮c由“9”旋转至“0” 3实验记录的t和R的数据见表 请根据表中数据在如图3所示的方格纸上作出R﹣t图象由图线求得R随t的变化关系为R=.
小明要利用多用电表和电阻箱测量电源的电动势和内阻. 1如图甲所示是多用电表内部结构的简化电路图内有3个档位对应3种测量功能.小明现要将其作为电流表使用选择开关S应接选填“1”“2”或“3”.小明调节好多用电表后连接电路如图乙所示是他正准备接入最后一根导线图中虚线所示时的实验电路.请指出图中在器材连接或操作上存在的两个不妥之处. 2调节电阻箱记录多组电阻箱示数R和多用电表示数I作出的图线如图丙所示.由此可求得电动势E=V内阻r=Ω.结果均保留2位有效数字 3本实验方案存在系统误差这是由于多用电表选填“分流”或“分压”而引起的测得的E测r测与真实值比较E测E真r测r真.选填“<”“=”或“>”
已知a>b>0则下列不等式成立的是
有机化合物G是抗肿瘤药物中一种关键的中间体由烃AC7H8合成G的路线如下部分反应条件及副产物已略去 已知以下信息 ①B比A的相对分子质量大79 ②D的分子式为C2H2O3可发生银镜反应且具有酸性. 回答下列问题 1测定有机物的组成和结构的现代分析方法中测定相对分子质量时使用的仪器名称是. 2A的名称是.由A生成B的化学方程式是. 3D中所含官能团的名称是. 4反应③④的反应类型分别是. 5下列说法不正确的是填选项序号. A.可用FeCl3溶液鉴别C和E B.有机物E中含有手性碳原子 C.B转化为C的第一步反应中的试剂甲为NaOH溶液 D.有机物E能发生加成反应不能发生缩聚反应 6G的同分异构体中符合下列要求的有种不考虑立体异构. ①属于芳香族化合物②既能发生银镜反应又能发生水解反应 7设计由丙酮酸为起始原料制备乙酸乙酯的合成路线无机试剂任选.合成反应流程图示例如下AB……H.
如图所示一束平行光以45°的入射角照射到半径为R的半圆柱形玻璃砖的上表面上已知玻璃砖对平行光的折射率为. ①圆柱面上光线能够射出的区域所对的圆心角θ是多少 ②能从圆柱面射出的光线中在玻璃砖中传播时间最长为多少光在真空中的速度为c
如图所示导体框位于竖直平面内匀强磁场垂直于纸面向里磁感应强度大小B=2.0T水平导体棒MN可沿两侧足够长的光滑导轨下滑而不分离导体棒MN质量m=0.1kg接入电路的电阻r=1.0Ω导轨宽度L=1.0m定值电阻R=3.0Ω装置的其余部分电阻可忽略不计.将导体棒MN无初速度释放导体棒下滑h=2.0m高度时速度达到最大重力加速度g=10m/s2.则导体棒
FiveyearsagowhenItaughtartataschoolinSeattleIusedTinkertoysasatestatthebeginningofatermtofindoutsomethingaboutmystudents.IputasmallsetofTinkertoysinfrontofeachstudentandsaid'MakesomethingoutoftheTinkertoys.Youhave45minutestoday﹣and45minuteseachdayfortherestoftheweek.'Afewstudentshesitatedtostart.Theywaitedtoseetherestoftheclasswoulddo.Severalotherscheckedtheinstructionsandmadesomethingaccordingtooneofthemodelplansprovided.Anothergroupbuiltsomethingoutoftheirownimaginations.OnceIhadaboywhoworkedexperimentallywithTinkertoysinhisfreetime.Hisconstructionsfilledashelfintheartclassroomandagoodpartofhisbedroomathome.Iwasdelightedatthepresenceofsuchastudent.Herewasanexceptionallycreativemindatwork.HispresencemeantthatIhadanunexpectedteachingassistantinclasswhosecreativitywouldinfect感染otherstudents.Encouragingthiskindofthinkinghasadownside.Irantheriskoflosingthosestudentswhohadadifferentstyleofthinking.Withoutfailonewoulddeclare'ButI'mjustnotcreative.''Doyoudreamatnightwhenyou'reasleep?''Ohsure.''Sotellmeoneofyourmostinterestingdreams.'Thestudentwouldtellsomethingwildlyimaginative.Flyingintheskyorinatimemachineorgrowingthreeheads.'That'sprettycreative.Whodoesthatforyou?''Nobody.Idoit.''Really﹣atnightwhenyou'reasleep?''Sure.''Trydoingitinthedaytimeinclassokay?'25.TheteacherusedTinkertoysinclassinorderto?A.knowmoreaboutthestudentsB.makethelessonsmoreexcitingC.raisethestudents'interestinartD.teachthestudentsabouttoydesign26.WhatdoweknowabouttheboymentionedinParagraph3?A.Helikedtohelphisteacher.B.Hepreferredtostudyalone.C.Hewasactiveinclass.D.Hewasimaginative.27.Whatdoestheunderlinedword'downside'inParagraph4probablymean?A.Mistake.B.Drawback.C.Difficulty.D.Burden.28.Whydidtheteacheraskthestudentstotalkabouttheirdreams?A.Tohelpthemtoseetheircreativity.B.Tofindoutabouttheirsleepinghabits.C.Tohelpthemtoimprovetheirmemory.D.Tofindoutabouttheirwaysofthinking.
某课外探究小组用如图所示实验装置测量学校所在位置的地磁场的水平分量Bx.将一段细长直导体棒南北方向放置并与开关导线电阻箱和电动势为E内阻为R的电源组成如图所示的电路.在导体棒正下方距离为l处放一小磁针开关断开时小磁针与导体棒平行现闭合开关缓慢调节电阻箱阻值发现小磁针逐渐偏离南北方向当电阻箱的接入阻值为5R时小磁针的偏转角恰好为30°.已知通电长直导线周围某点磁感应强度为B=kr为该点到通电长直导线的距离k为比例系数导体棒和导线电阻不计则该位置地磁场的水平分量大小为
如图所示倾角为37°的光滑斜面上粘贴有一厚度不计宽度为d=0.2m的橡胶带橡胶带的上表面与斜面位于同一平面内其上下边缘与斜面的上下边缘平行橡胶带的上边缘到斜面的顶端距离为L=0.4m现将质量为m=1kg质量分布均匀宽度为d的薄矩形板上边缘与斜面顶端平齐且从斜面顶端静止释放.已知矩形板与橡胶带之间的动摩擦因数为0.5重力加速度取g=10m/s2sin37°=0.6cos37°=0.8不计空气阻力矩形板由斜面顶端静止释放下滑到完全离开橡胶带的过程中此过程矩形板始终在斜面上下列说法正确的是
25分假定你是李华与留学生朋友John约好下周六下午一起去看电影因故不能赴约.请给他写封邮件内容包括 1.表示歉意 2.说明原因 3.另约时间. 注意1.词数100左右 2.可以适当增加细节以使行文连贯. .
如图所示△ABC为等腰直角三棱镜的截面图AB与水平屏幕MN垂直并接触于A点.由红光和紫光两种单色光组成的复色光垂直BC边射向AB中点O在光屏MN上产生两个亮斑已知该介质对红光和紫光的折射率分别为n1=n2=. 1请画出光路图并分析说出AM侧亮斑的颜色 2已知AB=10cm求两个亮斑间的距离.
如图所示有8个完全相同的长方体木板叠放在一起每个木板的质量为300g某人用手在这叠木板的两侧加一水平压力F使木板水平静止.若手与木板之间的动摩擦因数为0.5木板与木板之间的动摩擦因数为0.3最大静摩擦力等于滑动摩擦力g取10m/s2.则水平压力F至少为
地球的公转轨道接近圆但彗星的运动轨道则是一个非常扁的椭圆.天文学家哈雷曾经在1662年跟踪过一颗彗星他算出这颗彗星轨道的半长轴约等于地球公转半径的18倍并预言这颗彗星将每隔一定时间就会再次出现.这颗彗星最近出现的时间是1986年它下次飞近地球大约是哪一年
如图所示设月球半径为R假设“嫦娥四号”探测器在距月球表面高度为3R的圆形轨道Ⅰ上做匀速圆周运动运行周期为T到达轨道的A点时点火变轨进入椭圆轨道Ⅱ到达轨道的近月点B时再次点火进入近月轨道Ⅲ绕月做匀速圆周运动引力常量为G不考虑其他星球的影响则下列说法正确的是
如图在大气中有一水平放置的固定圆筒它由ab和c三个粗细不同的部分连接而成各部分的横截面积分别为2S和S.已知大气压强为p0温度为T0.两活塞A和B用一根长为4l的不可伸长的轻线相连把温度为T0的空气密封在两活塞之间此时两活塞的位置如图所示.现对被密封的气体加热使其温度缓慢上升到T.若活塞与圆筒壁之间的摩擦可忽略此时两活塞之间气体的压强可能为多少
15分一家英文报社面向中学生征文征文的主题是你身边的好人.假定你是李华请给该报社的编辑写封信推荐你们班的一位同学. 内容要点1.人物简介 2.推荐理由学习品质班级工作等 3.你的愿望. 注意1.词数100左右 2.可以适当增加细节以使行文连贯 3.开头和结尾已为你写好. Deareditor I'dliketorecommendagoodpersontoyou. Bestwishes! Yours LiHua.
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