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已知f′(x)是函数f(x)的导函数,且对任意的实数x都有f′(x)=ex(2x+3)+f(x)(e是自然对数的底数),f(0)=1,若不等式f(x)﹣k<0的解集中恰有两个整数,则实数k的取值范围...
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高三下学期数学《》真题及答案
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.已知函数fx是定义在R.上的可导函数其导函数记为f′x若对于任意实数x有fx>f′x且y=fx﹣1
(﹣∞,0)
(0,+∞)
(﹣∞,e
4
)
(e
4
,+∞)
已知函数fx=2x+k·2-xk∈R.1若函数fx为奇函数求实数k的值2若对任意的x∈[0+∞都有f
已知函数fx是定义在R.上的可导函数其导函数为f′x若对任意实数x有fx>f′x且y=fx﹣1的图象
已知函数fx的导函数为f'x且对任意的实数x都有e是自然对数的底数且f0=1若关于x的不等式fx﹣
已知定义在R.上的可导函数fx的导函数为f'x若对于任意实数x有fx-f'x>0且y=fx-1为奇函
(-∞,0)
(0,+∞)
(-∞,e
4
)
(e
4
,+∞)
已知函数fx对任意的实数x∈R.都有f1+x=-f-x且对任意的x1x2∈R.都有x1-x2[fx1
0
1
2
3
已知函数fx=ax2+bx+1a≠0对于任意x∈R.都有f1+x=f1﹣x且函数y=fx+2x为偶函
已知at为正实数函数fx=x2-2x+a且对任意的x∈[0t]都有fx∈[-aa].若对每一个正实数
已知函数fx的导函数为f'x且对任意的实数x都有e是自然对数的底数且f0=1若关于x的不等式fx﹣
已知函数fx的定义域为R且对任意的实数x导函数f′x满足0 1若对任意的闭区间[ab]R
设函数fx对任意实数x满足f1+x=αfx且f'0=β其中αβ为非零常数则
f(x)在x=1处不可导
f(x)在x=1处可导,且f'(1)=α
f(x)在x=1处可导,且f'(1)=β
f(x)在x=1处可导,且f'(1)=αβ
已知函数fx=2x+k•2﹣xk∈R.1若函数fx为奇函数求实数k的值.2若对任意的x∈[0+∞都有
设fx在-∞+∞上可导且对任意的x1和x2当x1>x2时都有fx1>fx2则______.
对任意x,f’(x)>0
对任意x,f’(-x)≤0
函数f(-x)单调增加
函数-f(-x)单调增加
已知函数fx=x2-2ax+5a>1.1若fx的定义域和值域均是[1a]求实数a的值2若fx在区间-
设fx是定义域为R.的偶函数且对任意实数x恒有fx+1=﹣fx已知x∈01时fx=1﹣x则函数fx在
是增函数,且f(x)<0
是增函数,且f(x)>0
是减函数,且f(x)<0
是减函数,且f(x)>0
已知at为正实数函数fx=x2-2x+a且对任意的x∈[0t]都有fx∈[-aa].若对每一个正实数
已知函数f'x是函数fx的导函数f1=e对任意实数x都有2fx﹣f'x>0则不等式的解集为.
已知函数fx=ax2+bx+1a≠0对于任意x∈R都有f1+x=f1﹣x且函数y=fx+2x为偶函数
已知定义在R.上的函数fx=x2+ax+b的图象经过原点且对任意的实数x都有f1+x=f1-x成立.
已知函数gx=ax3+2x2-2x函数fx是函数gx的导函数.1若a=1求gx的单调减区间2若对任意
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已知复数z满足z1﹣i=2﹣i其中i是虚数单位则复数z在复平面内对应的点位于
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It'sthattimeofyearagainwhenAlipayusjusthowmuchwe'vebeenspendingandonwhat. A.reminds B.reminded C.hasreminded D.isreminding
ThepolarbearisfoundintheArcticCircleandsomebiglandmassesasfarsouthasNewfoundland.Whiletheyarerarenorthof88°thereisevidence1theyrangeallthewayacrosstheArcticandasfarsouthasJamesBayinCanada.Itisdifficulttofigureoutaglobalpopulationofpolarbearsasmuchoftherangehasbeen2poorstudied;howeverbiologistscalculatethatthereareabout20000﹣25000polarbearsworldwide. Modernmethods3trackingpolarbearpopulationshavebeenemployedonlysincethemid﹣1980sandareexpensive4performconsistentlyoveralargearea.InrecentyearssomeInuitpeopleinNunayut5reportincreasesinbearsightingsaroundhumansettlementsleadingtoa6believethatpopulationsareincreasing.Scientistshaverespondedby7notethathungrybearsmaybecongregating聚集aroundhumansettlementsleadingtotheillusion错觉thatpopulationsare8highthantheyactuallyare.Of9nineteenrecognizedpolarbearsubpopulationsthreearedecliningsix10bestableoneisincreasingandninelackenoughdata.
IsFreshAirReallyGoodforYou? Weallgrewuphearingpeopletellustogooutandgetsomefreshair.1AccordingtorecentstudiestheanswerisabigYESiftheairqualityinyourcampingareaisgood. 2Iftheairyou'rebreathingisclean﹣whichitwouldbeifyou'reawayfromthesmogofcities﹣thentheairisfilledwithlife﹣givingenergizingoxygen.Ifyouexerciseoutofdoorsyourbodywilllearntobreathemoredeeplyallowingevenmoreoxygentogettoyourmuscles肌肉andyourbrain. Recentlypeoplehavebegunstudyingtheconnectionbetweenthenaturalworldandhealing治愈.3Intheseplacespatientscangotobenearnatureduringtheirrecovery.Itturnsoutthatjustlookingatgreengrowingthingscanreducestresslowerbloodpressureandputpeopleintoabettermood情绪.Greeneryisgoodforus.HospitalpatientsWhoseetreebranchesouttheirwindowarelikelytorecoveratafasterratethanpatientswhoseebuildingsorskyinstead.4Itgivesusagreatfeelingofpeace. 5Whilethesun'srayscanageandharmourskintheyalsogiveisbeneficialVitaminD.TomakesureyougetenoughVitaminD﹣butstillprotectyourskin﹣putonsunscreenrightasyouheadoutside.Ittakessunscreenaboutfifteenminutestostartworkingandthat'splentyoftimeforyourskintoabsorbaday'sworthofVitaminD. A.Freshaircleansourlungs. B.Sowhatareyouwaitingfor? C.Beinginnaturerefreshesus. D.Anothersidebenefitofgettingfreshairissunlight. E.Butisfreshairreallyasgoodforyouasyourmotheralwayssaid? F.Justasimportantlywetendtoassociateairwithhealthcare. G.AllacrossthecountryrecoverycentershavebegunbuildingHealingGardens.
Allchildrenshouldgetaccesstoahigh﹣qualityeducationtheirracezipcodeorfamilyincome. A.dueto B.regardlessof C.apartfrom D.dependingon
Thecreationcankeeppeopleawayfromtheirsmartphonesinawaysimilartoe﹣cigaretteshaveallowedpeopletoquitsmoking. A.that B.how C.which D.what
Goingtouniversityissupposedtobeamind﹣broadeningexperience.Thatassumptionispossiblymadeincontrasttotrainingforworkstraightafterschool.Butisitactuallytrue?JessikaGolleoftheUniversityofTubingenGermanythoughtshewouldtrytofindout.Herresulthoweverisnotquitewhatmightbeexpected.Itshowsthatthosewhohavebeentouniversitydoindeedseemtoleavewithbroaderandmoreinquiringmindsthanthosewhohavespenttheirimmediatepost﹣schoolyearsinvocationaltrainingforwork.Howeveritisnotthecasethatuniversitybroadensminds.Ratherworkseemstonarrowthem.Afterstudyingtheearlycareerof2095GermanyoungstersDr.Gollereachedtheconclusion.DuringtheperiodunderinvestigationGermanyhadthreetracksinitsschools:alowoneforpupilswhowouldmostprobablyleaveschoolearlyandentervocationaltraining;ahighoneforthosealmostcertaintoenteruniversity;andanintermediateonefromwhichtherewasachoicebetweentheacademicandvocationalroutes.Theteamusedtwostandardizedteststoassesstheirvolunteers.Onewasofpersonalitytraitsandtheotherofattitudes.Theyadministeredbothteststwice﹣oncetowardstheendofeachvolunteer'stimeatschoolandthenagainsixyearslater.Oftheoriginalgroup382wereontheintermediatetrackanditwasonthesethattheresearchersfocused.Ofthem212wenttouniversityandtheremaining170chosenforvocationaltrainingandajob.WhenitcametothesecondroundoftestsDrGollefoundthatthepersonalitiesofthosewhohadgonetouniversityhadnotapparentlychanged.Thosewhohadundergonevocationaltrainingandthengotjobswerenotthatmuchchangedinpersonalityeither﹣exceptinonecrucialrespect﹣theyhadbecomemoreresponsible.Thatsoundslikeagoodthingcomparedwiththecommonpublicimageofundergraduatesasabunchofpamperedlayabouts娇生惯养的闲人.Butchangesinattitudetheresearchersrecordedweremoreworrying.Intheuniversitygroupagainnoneweredetectable.Butthosewhohadchosenthevocationalrouteshowedmarkeddropsininterestintasksthatareinvestigativeandenterprisinginnature.Andthatmightrestricttheirchoiceofcareers.Someinvestigativeandenterprisingjobssuchasscientificresearchareindeedofflimitstothedegreeless.ButmanyparticularlyinGermanywithitstraditionofvocationaltrainingarenot.Theresearchersmentionforexamplecomputerprogrammersfinance﹣sectorworkersandentrepreneursascareersrequiringtheseattributes.IfDrGolleiscorrectandchangesinattitudebroughtaboutbytheverytrainingGermanypridesitselfonarenarrowingpeople'schoicesthatisindeedamatterofconcern.1Comparedwithstudentsgoingtouniversitythosechoosingthevocationalroute.A.showmorechangesintheirattitudesB.finditmoredifficulttolandsuitablejobsC.aremoreinterestedintasksrelatedtoscienceD.aremoreresponsibleanddotheirworkbetter2Theunderlinedword'detectable'inPara.9canbereplacedby.A.desirableB.predictableC.noticeableD.changeable3WhichofthefollowingisTRUEaccordingtothepassage?A.Universitygraduatesdon'tneedtoreceivetrainingatall.B.Germanyshouldchangethetraditionofvocationaltraining.C.Peoplewithoutadegreemayfindalimittotheirchoicesofcareers.D.Incomparisonwithvocationaltraininguniversitiescangreatlybroadenpeople'sminds.4Inwhichcolumnofamagazinecanyoufindthepassage?A.Science.B.Culture.C.Economy.D.Education.
1Inwhichrestaurantcanyouhaveamealwithpeacefulcountrysurroundings?A.CHANGTOMTHAIRESTAURANTANDHOTELB.JACK'STRADITIONALANDAMERICANRESTAURANTC.MOGHULEXPRESSINDIANTAKEAWAYD.THEMARINARESTAURANT2Itcanbeconcludedthat.A.youcanenjoythefreshestlocalproduceinCHANGTOMTHAIRESTAURANTANDHOTELB.JACK'STRADITIONALANDAMERICANRESTAURANTsatisfiesalldifferenttastesC.youcanhaveyourorderdeliveredinMOGHULEXPRESSINDIANTAKEAWAYforanextrafeeD.THEMARINARESTAURANTprovidesthebestaccommodationofthefourrestaurants
﹣ThesewinterdaysaregettingtobemorethanIcantake. ﹣Holdon.Accordingtotheweatherreportpeoplehavesomereliefbytheendoftheweek. A.would B.should C.need D.shall
IamimpressedwithChina'scommitmenttoitsclimategoalsevidencedbythefactwearesureofChinahasmetits2020targetsthreeyearsaheadofschedule. A.that B.which C.what D.where
NeedaJobThisSummer?Theprovincialgovernmentanditspartnersoffermanyprogramstohelpstudentsfindsummerjobs.Thedeadlinesandwhatyouneedtoapplydependontheprogram.Notastudent?Gotothegovernmentwebsitetolearnaboutprogramsandonlinetoolsavailabletohelppeopleunder30buildskillsfindajoborstartbusinessesallyearround.JobsforYouthIfyouareateenagerlivingincertainpartsoftheprovinceyoucouldbeeligible符合条件forthisprogramWhichprovideseightweeksofpaidemploymentalongwithtraining.Whoiseligible:Youth15﹣18yearsoldinselectcommunities社区.SummerCompanySummerCompanyprovidesstudentswithhands﹣onbusinesstrainingandawardsofupto$3000tostartandruntheirownsummerbusinesses.Whoiseligible:Studentsaged15﹣29returningtoschoolinthefall.StewardshipYouthRangerProgramYoucouldapplytobeaStewardshipYouthRangerandworkonlocalnaturalresourcemanagementprojectsforeightweeksthissummer.Whoiseligible:Studentsaged16or17attimeofhirebutnotturning18beforeDecember31thisyear.SummerEmploymentOpportunities机会ThroughtheSummerEmploymentOpportunitiesprogramstudentsarehiredeachyearinavarietyofsummerpositionsacrosstheProvincialPublicServiceitsrelatedagenciesandcommunitygroups.Whoiseligible:Studentsaged15orolder.Somepositionsrequirestudentstobe15to24orupto29forpersonswithadisability.1WhatisspecialaboutSummerCompany?A.Itrequiresnotrainingbeforeemployment.B.Itprovidesawardsforrunningnewbusinesses.C.Itallowsonetoworkinthenaturalenvironment.D.Itoffersmoresummerjobopportunities.2WhatistheagerangerequiredbyStewardshipYouthRangerProgram?A.15﹣18.B.15﹣24.C.15﹣29.D.16﹣17.3Whichprogramfavorsthedisabled?A.JobsforYouth.B.SummerCompany.C.StewardshipYouthRangerProgram.D.SummerEmploymentOpportunities.
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