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设f(t)连续，区域D=(x，y)||x|≤1，|y|≤1，求证：
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设fxgx为连续可微函数且存在uxy使得du=yfxydx+xgxydy求fx-gx．
Ⅰ设D=xy|a≤x≤bc≤y≤d|若fxy与fyx在D上连续证明Ⅱ设D为Oxy平面上的区域若fxy
设z=yx则=
xyx
-1
lnx
yx
-1
(x+lny)
yx
-1
(xlny+1)
yln
2
y
设曲线Lfxy=1fxy具有一阶连续偏导数过第二象限内的点M和第四象限内的点NΓ为L上从点M到点N的
∫
Γ
f(x，y)dx．
∫
Γ
f(x，y)dy．
∫
Γ
f(x，y)ds．
∫
Γ
f’
x
(x，y)dx+f’
y
(x，y)dy．
设fx在积分区间上连续则sinx［fx+f-x］dx等于
-1
1
2
设fx二阶连续可导且f0=0f’0=1求uxy使du=y[fx+3e2x]dx+f’xdy．
设函数fu连续区域D=xy|x2+y2≤2y则等于
A
B
C
D
设z=yx则=
xyx
-1
lnx
yx
-1
（x+lny）
yx
-1
（xlny+1）
yln
2
y
设二维连续型随机变量XY在矩形区域D=xy|0≤x≤20≤y≤1上服从均匀分布令Z=maxXY求EZ
不可压缩流体平面流动在y方向的速度分量为uy=y2-2x+2y根据连续性方程可知速度在x方向的分量u
-（2yx+2x）+f（y）
2x（y+1）
-（2yx+2y）+f（x）
2x（y+1）+c
设随机变量X1和X2不相关且DX1=DX2=σ2≠0令X=X1+aX2Y=X1+bX2ab≠0如果X
a与b可以是任意实数．
a=b．
ab=-1．
ab=1．
设fx在[1+∞上连续若曲线y=fx直线x=1x=tt＞1与x轴围成的平面区域绕x轴旋转一周所得的旋
不可压缩流体平面流动在y方向的速度分量为uy=y2-2x+2y根据连续性方程可知速度在x方向的分量u
-(2yx+2x)+f(y)
2x(y+1)
-(2yx+2y)+f(x)
2x(y+1)+c
设fx有连续一阶导数xy-yfxdx+fx+y2dy=duxy求fx及uxy其中f0=-1．
下列命题①设∫fxdx=Fx+C则对任意函数gx有∫f[gx]dx=F[gx]+C ②设函数fx在
(A) ①、③．
(B) ①、④．
(C) ②、③．
(D) ②、④．
设y＝fx为区间[01]上的连续函数且恒有0≤fx≤1可以用随机模拟方法近似计算积分dx.先产生两组
设随机变量XY不相关且EX=2EY=1DX=3则E[XX+Y-2]=
-3
3
-5
5
设fx是连续函数若ʃfxdx＝1ʃfxdx＝－1则ʃfxdx＝________.
设D为Oxy平面上的区域若fxy与fyx都在D上连续证明fxy与fyx在D上相等．
设fx在积分区间上连续则sin[fx+f-x］dx等于
0
1
-1
2
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Directions:Atpresentmuchattentionisbeingattachedtotheenvironmentalprotection.Writealettertoadvocatecar-pooling.Andinyourletteryoushouldatleaststatetheaimofyourwritingandtheadvantagesofcar-pooling.Youshouldwriteabout100wordsonANSWERSHEET2.Donotsignyourownnameattheendoftheletter.UseLiMinginstead.Youdonotneedtowritetheaddress.
设a为常数则数列极限=______．
[A]DrDanielStanleyanoceanographerhasfoundvolcanicshardsinEgyptthathebelievesarelinkedtotheexplosion.ComputersimulationsbyMikeRampinoaclimatemodelerfromNewYorkUniversityshowthattheresultingashcloudcouldhaveplungedtheareaintodarknessaswellasgeneratinglightningandhailtwoofthe10plagues. [B]Thecloudcouldhavealsoreducedtherainfallcausingadrought.IftheNilehadthenbeenpoisonedbytheeffectsoftheeruptionpollutioncouldhaveturneditredashappenedinarecentenvironmentaldisasterinAmerica.Thesamepollutioncouldhavedrivenmillionsoffrogsontothelandthesecondplague.Onlandthefrogswoulddieremovingtheonlyobstacletoanexplosionoffliesandlice—thethirdandfourthplagues.Thefliescouldhavetransmittedfataldiseasestocattlethefifthplagueandboilsandblisterstohumansthesixthplague. [C]MoseswhichwillbebroadcastinDecember2002willsuggestthatmuchoftheBiblestorycanheexplainedbyasinglenaturaldisasterahugevolcaniceruptionontheGreekislandofSantoriniinthe16thcenturyBC. [D]Thehour-longdocumentaryarguesthateventhestoryofthepartingoftheRedSeawhichallowedMosestoleadtheHebrewstosafetywhilethepursuingEgyptianarmywasdrownedmayhaveitsoriginsintheeruption.Itrepeatsthetheorythat"RedSea"isamistranslationoftheSeaofReedsamuchshallowerswamp. [E]TheprogrammetellsthestoryofhowMosesledtheHebrewsoutofEgyptafteraseriesofplagueshaddevastatedthecountry.Butitalsousesnewscientificresearchtoarguethatmanyoftheeventssurroundingtheexoduscouldhavebeentriggeredbytheeruptionwhichwouldhavebeenathousandtimesmorepowerfulthananuclearbomb. [F]ComputersimulationsshowthattheSantorinieruptioncouldhavetriggereda600ft-hightidalwavetravelingatabout400milesanhourwhichwouldhavebeen6fthighandahundredmileslongwhenitreachedtheEgyptiandelta.Suchaneventwouldhavebeenrememberedforgenerationsandmayhaveprovidedtheinspirationforthestory. [G]FreshevidencethattheBiblicalplaguesandthepartingoftheRedSeawerenaturaleventsratherthanmythsormiraclesistobepresentedinanewBBCdocumentary. Order: 41
设fx在x=0的某邻域内有定义且满足求极限
Apairofdicerolledagainandagainwilleventuallyproducetwosixes.Similarlythevirusthatcausesinfluenzaisconstantlychangingatrandomandonedaywillmutateinawaythatwillenableittoinfectbillionsofpeopleandtokillmillions.Manyexpertsnowbelieveaglobaloutbreakofpandemicfluisoverdueandthatthenextonecouldbeasbadastheonein1918whichkilledsomewherebetween25mand50mpeople.Todayhoweveradvancesinmedicineofferrealhopethatanothersuchoutbreakcanbecontained—ifgovernmentsstartpreparingnow.Newresearchpublishedthisweeksuggeststhatarelativelysmallstockpileofanantiviraldrug—aslittleas3mdoses—couldbeenoughtolimitsharplyaflupandemicifthedrugsweredeployedquicklytopeopleintheareasurroundingtheinitialoutbreak.Thedrug’smanufacturerRocheistalkingtotheWorldHealthOrganisationaboutdonatingsuchastockpile.Thisisgoodnews.ButmuchmoreneedstobedoneespeciallywithanastystrainofavianfluspreadinginAsiawhichcouldmutateintoathreattohumans.SincetheSARSoutbreakin2003afewcountrieshavedevelopedplansinpreparationforsimilarepisodes.Butprogresshasbeenshamefullypatchyandthereisstillfartoolittleinternationalcoordination.Aglobalstockpileofdrugsalonewouldnotbemuchusewithoutanadequatesystemofsurveillancetoidentifyearlycasesandawayofdeliveringtreatmentquickly.Ifanoutbreakoccurredinaborderregionforexampleaswiftresponsewouldmostlikelydependonprioragreementsbetweendifferentcountriesaboutquarantineandcontainment.Reachingsuchagreementsisrarelyeasybutthatmakesthetaskallthemoreurgent.Richcountriestendtobebetterpreparedthanpooronesbutthisshouldbenoconsolationtothem.Fludoesnotrespectborders.Itisineveryone’sinteresttomakesurethatdevelopingcountriesespeciallyinAsiaarealsowellprepared.Manymaybridleatinterferencefromoutside.Butifrichernationswerewillingtodonateanti-viraldrugsandguaranteeasupplyofanyvaccinethatbecomesavailablepoorernationsmightbewillingtoreachagreementsoversurveillanceandpreparedness.Simplysortingoutafewdetailsnowwillhavelivesandrecriminationslater.WilltherebeenoughventilatorsmakesanddrugsWherewillpeoplebetreatedifthehospitalsoverflowWillfoodbedeliveredasnormalToomanycountrieshavenoanswerstothesequestions.ThewordcontainedLine6Paragraph1mostprobablymeans______.
设B是3阶非零矩阵且满足BA=0．Ⅰ求矩阵BⅡ如果矩阵B的第1列是12-3T求B-E6．
求椭圆5x2+8xy+5y2=9的长短半轴之长．
设函数fx满足f'0=0f0＜0则存在δ＞0使得
设二元函数fuv具有二阶连续偏导数且满足又gxy=fx2-y22xy则=______．
设半径为1的球正好有一半沉入水中球的比重为1现将球从水中取出问要作多少功假设在球从水中取出的过程中水面的高度不变．
[A]DrDanielStanleyanoceanographerhasfoundvolcanicshardsinEgyptthathebelievesarelinkedtotheexplosion.ComputersimulationsbyMikeRampinoaclimatemodelerfromNewYorkUniversityshowthattheresultingashcloudcouldhaveplungedtheareaintodarknessaswellasgeneratinglightningandhailtwoofthe10plagues. [B]Thecloudcouldhavealsoreducedtherainfallcausingadrought.IftheNilehadthenbeenpoisonedbytheeffectsoftheeruptionpollutioncouldhaveturneditredashappenedinarecentenvironmentaldisasterinAmerica.Thesamepollutioncouldhavedrivenmillionsoffrogsontothelandthesecondplague.Onlandthefrogswoulddieremovingtheonlyobstacletoanexplosionoffliesandlice—thethirdandfourthplagues.Thefliescouldhavetransmittedfataldiseasestocattlethefifthplagueandboilsandblisterstohumansthesixthplague. [C]MoseswhichwillbebroadcastinDecember2002willsuggestthatmuchoftheBiblestorycanheexplainedbyasinglenaturaldisasterahugevolcaniceruptionontheGreekislandofSantoriniinthe16thcenturyBC. [D]Thehour-longdocumentaryarguesthateventhestoryofthepartingoftheRedSeawhichallowedMosestoleadtheHebrewstosafetywhilethepursuingEgyptianarmywasdrownedmayhaveitsoriginsintheeruption.Itrepeatsthetheorythat"RedSea"isamistranslationoftheSeaofReedsamuchshallowerswamp. [E]TheprogrammetellsthestoryofhowMosesledtheHebrewsoutofEgyptafteraseriesofplagueshaddevastatedthecountry.Butitalsousesnewscientificresearchtoarguethatmanyoftheeventssurroundingtheexoduscouldhavebeentriggeredbytheeruptionwhichwouldhavebeenathousandtimesmorepowerfulthananuclearbomb. [F]ComputersimulationsshowthattheSantorinieruptioncouldhavetriggereda600ft-hightidalwavetravelingatabout400milesanhourwhichwouldhavebeen6fthighandahundredmileslongwhenitreachedtheEgyptiandelta.Suchaneventwouldhavebeenrememberedforgenerationsandmayhaveprovidedtheinspirationforthestory. [G]FreshevidencethattheBiblicalplaguesandthepartingoftheRedSeawerenaturaleventsratherthanmythsormiraclesistobepresentedinanewBBCdocumentary. Order: 43
Companieshaveembarkedonwhatlookslikethebeginningsofare-runofthemergersandacquisitionsM＆Awavethatdefinedthesecondbubblyhalfofthe1990s.Thatperiodreadersmightrecallwascharacterizedbyacollectivesplurgethatsawthecreationofsomeofthemostindebtedcompaniesinhistorymanyofwhichlaterwentbankruptorwerethemselvesbrokenup.WildbiddingfortelecomsinternetandmediaassetsnottomentionthemadnessthatwasDaimler’s$40billionmotoringtakeoverin1998-1999ofChryslerortheTime-Warner/AOLmega-mergerin2000helpedtogivemergersathoroughlybadname.AconsensusemergedthatM＆Awasagreatwayforinvestmentbankstoreaprichfeesandasurewayforambitiousmanagerstobetrayinvestorsbytrashingthevalueoftheirshares.NowM＆Aisback.ItsreturnisaglobalphenomenonbutitisperhapsmoststrikinginEuropewheresofarthisyeartherehasbeenastreamofdealsworthmorethan$600billionintotalaround40%higherthaninthesameperiodof2004.ThelatesteffortcamethisweekwhenFrance’sSaint-Gobainabuilding-materialsfirmunveiledthedetailsofits￡3.6billion$6.5billionhostilebidforBPBaBritishrival.Inthefirsthalfoftheyearcross-borderactivitywasupthreefoldoverthesameperiodlastyear.EvenFranceTelecomwhichwasleftalmostbankruptattheendofthelastmergerwaverecentlyboughtAmenaaSpanishmobileoperator.Shareholder’sapprovalofallthesedealsraisesaninterestingquestionforcompanieseverywhere:areinvestorsrighttothinkthinthesemergersaremorelikelytosucceedthanearlieronesTherearetwoanswers.Thefirstisthatpastmergersmayhavebeenjudgedtooharshly.ThesecondisthatthepresentrashofEuropeandealsdoeslookmorerationalbut—andthecaveatiscrucial—onlysofar.Thepatternmaynothold.M＆A’spoorreputationstemsnotonlyfromthestringofspectacularfailuresinthe1990sbutalsofromstudiesthatshowedvaluedestructionforacquiringshareholdersin80%ofdeals.Butmorerecentstudiesbyeconomistshaveintroducedanoteofcaution.Investorsshouldlookatthenumberofdealsthatsucceedorfailtypicallymeasuredbytheimpactonthesharepriceratherthanasyoumightthinkweighingthembysize.ForexamplenoonedoubtsthattheDaimler-Chryslermergerdestroyedvalue.ThecombinedmarketvalueofthetwofirmsisstillbelowthatofDaimleralonebeforethedeal.ThissingledealaccountedforhalfofallGermanM＆Aactivitybyvaluein1998and1999andprobablydominatedpeople’sthinkingaboutmergerstothesamedegree.Throwinafewothersuchmonstersanditisnowonderthatbroadstudieshavetendedtofindthatmergersareabadidea.Thetruepictureismorecomplicated.Thepatterninthethirdparagraphmostprobablydenotes______.
曲线在t=0对应点处切线的直角坐标方程是______．
求常数k的取值范围使得不等式kln1+x＞arctanx当x＞0时成立．
作自变量替换把方程变换成y关于t的微分方程并求原方程的通解．
Inthepastyearalothaschangedinthefieldofhumanspaceflight.46InJanuaryPresidentGeorgeBushbrushedasidethefactthatAmerica’sentirespace-shuttlefleetwasgroundedwhenheannouncedgrandioseplanstoputpeoplebackonthemoonandthentolaunchamannedmissiontoMars.47InJuneButtRutananAmericanaeronauticalengineershowedthathumanspaceflightwasnolongerthepreserveofgovernmentsbysendingamantotheedgeofspaceinSpaceShipOneaprivatelyfinancedvehiclethatcostaboutthesametobuildasaluxuryyacht.ThatwasfollowedinSeptemberbySirRichardBransontheBritishentrepreneurbehindtheVirginbrandannouncingthathehadsignedadealwithMrRutantoworkonplansforafleetoffivesuborbitalvehiclesdevelopedfromSpaceShipOne. 48NowinthedyingdaysoftheyearAmerica’sCongresshaspassedabillthatunravelsatangleaboutwhowouldberesponsibleforregulatingthefledglingindustryandunderwhatterms.49ThebillalsoallowspassengerstoflyontheunderstandingthatthisnewgenerationofvehiclesmaynotbeassafeastakingacommercialflightbetweensayNewYorkandLondon. TheofficiallinefromVirginGalacticaasSirRichard’slatestventureismodestlynamedisthatthiscomingchangeinthelawmakesnopracticaldifferencetothefirm’splanssincetheydonotintendtoflyunlesstheycanmaketheirspacecraftassafeasaprivatejet.Butitmustsurelycomeassomesortofrelief.InanycaseWillWhitehorndirectorofcorporateaffairsatVirgin’sheadquartersinLondonandsoontobecomethepresidentofVirginGalacticasaysthatworkisunderwayonamockupoftheinteriorofanewspacecraftthatwillholdfivepassengers.50Virginhasalreadycommitted$20mtowardslicensingtheSpaceShipOnetechnologyfromMr.RutanandhisfinancialbackerPaulAllenasoftwarebillionaire. 49
设fx在[0+∞连续在0+∞可导x∈0+∞时fx＞0且单调上升x=gy为y=fx的反函数它们满足则fx的表达式是______．
Apairofdicerolledagainandagainwilleventuallyproducetwosixes.Similarlythevirusthatcausesinfluenzaisconstantlychangingatrandomandonedaywillmutateinawaythatwillenableittoinfectbillionsofpeopleandtokillmillions.Manyexpertsnowbelieveaglobaloutbreakofpandemicfluisoverdueandthatthenextonecouldbeasbadastheonein1918whichkilledsomewherebetween25mand50mpeople.Todayhoweveradvancesinmedicineofferrealhopethatanothersuchoutbreakcanbecontained—ifgovernmentsstartpreparingnow.Newresearchpublishedthisweeksuggeststhatarelativelysmallstockpileofanantiviraldrug—aslittleas3mdoses—couldbeenoughtolimitsharplyaflupandemicifthedrugsweredeployedquicklytopeopleintheareasurroundingtheinitialoutbreak.Thedrug’smanufacturerRocheistalkingtotheWorldHealthOrganisationaboutdonatingsuchastockpile.Thisisgoodnews.ButmuchmoreneedstobedoneespeciallywithanastystrainofavianfluspreadinginAsiawhichcouldmutateintoathreattohumans.SincetheSARSoutbreakin2003afewcountrieshavedevelopedplansinpreparationforsimilarepisodes.Butprogresshasbeenshamefullypatchyandthereisstillfartoolittleinternationalcoordination.Aglobalstockpileofdrugsalonewouldnotbemuchusewithoutanadequatesystemofsurveillancetoidentifyearlycasesandawayofdeliveringtreatmentquickly.Ifanoutbreakoccurredinaborderregionforexampleaswiftresponsewouldmostlikelydependonprioragreementsbetweendifferentcountriesaboutquarantineandcontainment.Reachingsuchagreementsisrarelyeasybutthatmakesthetaskallthemoreurgent.Richcountriestendtobebetterpreparedthanpooronesbutthisshouldbenoconsolationtothem.Fludoesnotrespectborders.Itisineveryone’sinteresttomakesurethatdevelopingcountriesespeciallyinAsiaarealsowellprepared.Manymaybridleatinterferencefromoutside.Butifrichernationswerewillingtodonateanti-viraldrugsandguaranteeasupplyofanyvaccinethatbecomesavailablepoorernationsmightbewillingtoreachagreementsoversurveillanceandpreparedness.Simplysortingoutafewdetailsnowwillhavelivesandrecriminationslater.WilltherebeenoughventilatorsmakesanddrugsWherewillpeoplebetreatedifthehospitalsoverflowWillfoodbedeliveredasnormalToomanycountrieshavenoanswerstothesequestions.Thespeedo{remedydispatchisofimportanceto______.
Apairofdicerolledagainandagainwilleventuallyproducetwosixes.Similarlythevirusthatcausesinfluenzaisconstantlychangingatrandomandonedaywillmutateinawaythatwillenableittoinfectbillionsofpeopleandtokillmillions.Manyexpertsnowbelieveaglobaloutbreakofpandemicfluisoverdueandthatthenextonecouldbeasbadastheonein1918whichkilledsomewherebetween25mand50mpeople.Todayhoweveradvancesinmedicineofferrealhopethatanothersuchoutbreakcanbecontained—ifgovernmentsstartpreparingnow.Newresearchpublishedthisweeksuggeststhatarelativelysmallstockpileofanantiviraldrug—aslittleas3mdoses—couldbeenoughtolimitsharplyaflupandemicifthedrugsweredeployedquicklytopeopleintheareasurroundingtheinitialoutbreak.Thedrug’smanufacturerRocheistalkingtotheWorldHealthOrganisationaboutdonatingsuchastockpile.Thisisgoodnews.ButmuchmoreneedstobedoneespeciallywithanastystrainofavianfluspreadinginAsiawhichcouldmutateintoathreattohumans.SincetheSARSoutbreakin2003afewcountrieshavedevelopedplansinpreparationforsimilarepisodes.Butprogresshasbeenshamefullypatchyandthereisstillfartoolittleinternationalcoordination.Aglobalstockpileofdrugsalonewouldnotbemuchusewithoutanadequatesystemofsurveillancetoidentifyearlycasesandawayofdeliveringtreatmentquickly.Ifanoutbreakoccurredinaborderregionforexampleaswiftresponsewouldmostlikelydependonprioragreementsbetweendifferentcountriesaboutquarantineandcontainment.Reachingsuchagreementsisrarelyeasybutthatmakesthetaskallthemoreurgent.Richcountriestendtobebetterpreparedthanpooronesbutthisshouldbenoconsolationtothem.Fludoesnotrespectborders.Itisineveryone’sinteresttomakesurethatdevelopingcountriesespeciallyinAsiaarealsowellprepared.Manymaybridleatinterferencefromoutside.Butifrichernationswerewillingtodonateanti-viraldrugsandguaranteeasupplyofanyvaccinethatbecomesavailablepoorernationsmightbewillingtoreachagreementsoversurveillanceandpreparedness.Simplysortingoutafewdetailsnowwillhavelivesandrecriminationslater.WilltherebeenoughventilatorsmakesanddrugsWherewillpeoplebetreatedifthehospitalsoverflowWillfoodbedeliveredasnormalToomanycountrieshavenoanswerstothesequestions.Thebesttitleforthetextwouldbe______.
=______．
设fx在[01]上连续在01内二次可导且fx在[01]上的最大值M=2最小值m=0求证若fx的最大值点或最小值点至少有一个是区间01内的点则在01内必存在两点ξ与η使得|f’ξ|＞2|fη|＞4成立．
Manycountrieshaveatraditionofinvitingforeignerstorulethem.TheEnglishcalledinWilliamofOrangein1688anddependingonyourinterpretationofhistoryWilliamofNormandyin1066.Bothdidratheragoodjob.ReturningthecomplimentAlbaniaaskedawell-bredEnglishmancalledAubgreyHerberttobetheirkinginthe1920s.Herefused—andtheyendedupwithseveralcovescalledZog.Americathecountryofimmigrantshasnotruckwithimportedforeigntalent.ArticletwooftheConstitutionsaysthatnopersonexceptanatural-borncitizen...shallbeeligibletotheofficeofthepresident.Thisisnowbeingchallengedbyaparticularlyirresistibleimmigrant:ArnoldSchwarzenegger.BarelyayearhaspassedsincetheerstwhilecyborgswepttovictoryinCalifornia’srecallelectionyetthereisalreadyanAmend-for-ArnoldcampaigncollectingsignaturestolettheAustrian-borngovernorhaveagoattheWhiteHouse.GeorgeBushseniorhasweighedinonhisbehalf.ThereareseveralArnoldamendmentsinCongress:oneallowsforeignerswhohavebeennaturalizedcitizensfor20yearstobecomepresident.TheAustrianbecameAmericanin1983.Itiseasytodismissthehooplaasanotherregrettableexampleofloopycelebritypolitics.Mr.Schwarzeneggerhasmadeadecentstartasgovernorbuthehasdonelittleasyettochangethestructureofhisdysfunctionalstate.IndeedevenifthelawwerechangedhecouldwellbeelbowedasidebyanotherincomerthistimefromCanada:theDemocraticgovernorofMichiganJenniferGranholmwhoappearstohavefewerskeletonsinherclosetthanthehedonisticactor.MoreoverchangingtheAmericanconstitutionisnododdle.Ithashappenedonly17timessince1791whenthefirsttenamendmentswerecodifiedasthebillofrights.Tochangetheconstitutionanamendmenthastobeapprovedbytwo-thirdsofbothhousesofCongressandthentoberatifiedbythree-quartersofthe50states.TheArnoldamendmentishardlyinthesamecategoryasabolishingslaveryorgivingwomenthevote.AndassomewagspointoutAustrianimportshaveaprettydodgyrecordofrunningmilitarysuperpowers.ThephrasehasnotruckwithLine1Paragraph2mostprobablymeans______.
若f-10为函数fxy=e-xax+b-y2的极大值则常数ab应满足的条件是______．
Manycountrieshaveatraditionofinvitingforeignerstorulethem.TheEnglishcalledinWilliamofOrangein1688anddependingonyourinterpretationofhistoryWilliamofNormandyin1066.Bothdidratheragoodjob.ReturningthecomplimentAlbaniaaskedawell-bredEnglishmancalledAubgreyHerberttobetheirkinginthe1920s.Herefused—andtheyendedupwithseveralcovescalledZog.Americathecountryofimmigrantshasnotruckwithimportedforeigntalent.ArticletwooftheConstitutionsaysthatnopersonexceptanatural-borncitizen...shallbeeligibletotheofficeofthepresident.Thisisnowbeingchallengedbyaparticularlyirresistibleimmigrant:ArnoldSchwarzenegger.BarelyayearhaspassedsincetheerstwhilecyborgswepttovictoryinCalifornia’srecallelectionyetthereisalreadyanAmend-for-ArnoldcampaigncollectingsignaturestolettheAustrian-borngovernorhaveagoattheWhiteHouse.GeorgeBushseniorhasweighedinonhisbehalf.ThereareseveralArnoldamendmentsinCongress:oneallowsforeignerswhohavebeennaturalizedcitizensfor20yearstobecomepresident.TheAustrianbecameAmericanin1983.Itiseasytodismissthehooplaasanotherregrettableexampleofloopycelebritypolitics.Mr.Schwarzeneggerhasmadeadecentstartasgovernorbuthehasdonelittleasyettochangethestructureofhisdysfunctionalstate.IndeedevenifthelawwerechangedhecouldwellbeelbowedasidebyanotherincomerthistimefromCanada:theDemocraticgovernorofMichiganJenniferGranholmwhoappearstohavefewerskeletonsinherclosetthanthehedonisticactor.MoreoverchangingtheAmericanconstitutionisnododdle.Ithashappenedonly17timessince1791whenthefirsttenamendmentswerecodifiedasthebillofrights.Tochangetheconstitutionanamendmenthastobeapprovedbytwo-thirdsofbothhousesofCongressandthentoberatifiedbythree-quartersofthe50states.TheArnoldamendmentishardlyinthesamecategoryasabolishingslaveryorgivingwomenthevote.AndassomewagspointoutAustrianimportshaveaprettydodgyrecordofrunningmilitarysuperpowers.ThewordcyborgLine1Paragraph3mostprobablyrefersto______.
Companieshaveembarkedonwhatlookslikethebeginningsofare-runofthemergersandacquisitionsM＆Awavethatdefinedthesecondbubblyhalfofthe1990s.Thatperiodreadersmightrecallwascharacterizedbyacollectivesplurgethatsawthecreationofsomeofthemostindebtedcompaniesinhistorymanyofwhichlaterwentbankruptorwerethemselvesbrokenup.WildbiddingfortelecomsinternetandmediaassetsnottomentionthemadnessthatwasDaimler’s$40billionmotoringtakeoverin1998-1999ofChryslerortheTime-Warner/AOLmega-mergerin2000helpedtogivemergersathoroughlybadname.AconsensusemergedthatM＆Awasagreatwayforinvestmentbankstoreaprichfeesandasurewayforambitiousmanagerstobetrayinvestorsbytrashingthevalueoftheirshares.NowM＆Aisback.ItsreturnisaglobalphenomenonbutitisperhapsmoststrikinginEuropewheresofarthisyeartherehasbeenastreamofdealsworthmorethan$600billionintotalaround40%higherthaninthesameperiodof2004.ThelatesteffortcamethisweekwhenFrance’sSaint-Gobainabuilding-materialsfirmunveiledthedetailsofits￡3.6billion$6.5billionhostilebidforBPBaBritishrival.Inthefirsthalfoftheyearcross-borderactivitywasupthreefoldoverthesameperiodlastyear.EvenFranceTelecomwhichwasleftalmostbankruptattheendofthelastmergerwaverecentlyboughtAmenaaSpanishmobileoperator.Shareholder’sapprovalofallthesedealsraisesaninterestingquestionforcompanieseverywhere:areinvestorsrighttothinkthinthesemergersaremorelikelytosucceedthanearlieronesTherearetwoanswers.Thefirstisthatpastmergersmayhavebeenjudgedtooharshly.ThesecondisthatthepresentrashofEuropeandealsdoeslookmorerationalbut—andthecaveatiscrucial—onlysofar.Thepatternmaynothold.M＆A’spoorreputationstemsnotonlyfromthestringofspectacularfailuresinthe1990sbutalsofromstudiesthatshowedvaluedestructionforacquiringshareholdersin80%ofdeals.Butmorerecentstudiesbyeconomistshaveintroducedanoteofcaution.Investorsshouldlookatthenumberofdealsthatsucceedorfailtypicallymeasuredbytheimpactonthesharepriceratherthanasyoumightthinkweighingthembysize.ForexamplenoonedoubtsthattheDaimler-Chryslermergerdestroyedvalue.ThecombinedmarketvalueofthetwofirmsisstillbelowthatofDaimleralonebeforethedeal.ThissingledealaccountedforhalfofallGermanM＆Aactivitybyvaluein1998and1999andprobablydominatedpeople’sthinkingaboutmergerstothesamedegree.Throwinafewothersuchmonstersanditisnowonderthatbroadstudieshavetendedtofindthatmergersareabadidea.Thetruepictureismorecomplicated.Theconclusionreachedbygeneralresearchesisthatmergersarenot______.
设αβ都是n维非零列向量矩阵A=2E-αβT其中E是n阶单位矩阵．若A2=A+2E则αTβ=______．
设A是n阶反对称矩阵Ⅰ证明A可逆的必要条件是n为偶数当n为奇数时A*是对称矩阵Ⅱ举一个4阶不可逆的反对称矩阵的例子Ⅲ证明如果λ是A的特征值那么-λ也必是A的特征值．
求累次积分．
Inthepastyearalothaschangedinthefieldofhumanspaceflight.46InJanuaryPresidentGeorgeBushbrushedasidethefactthatAmerica’sentirespace-shuttlefleetwasgroundedwhenheannouncedgrandioseplanstoputpeoplebackonthemoonandthentolaunchamannedmissiontoMars.47InJuneButtRutananAmericanaeronauticalengineershowedthathumanspaceflightwasnolongerthepreserveofgovernmentsbysendingamantotheedgeofspaceinSpaceShipOneaprivatelyfinancedvehiclethatcostaboutthesametobuildasaluxuryyacht.ThatwasfollowedinSeptemberbySirRichardBransontheBritishentrepreneurbehindtheVirginbrandannouncingthathehadsignedadealwithMrRutantoworkonplansforafleetoffivesuborbitalvehiclesdevelopedfromSpaceShipOne. 48NowinthedyingdaysoftheyearAmerica’sCongresshaspassedabillthatunravelsatangleaboutwhowouldberesponsibleforregulatingthefledglingindustryandunderwhatterms.49ThebillalsoallowspassengerstoflyontheunderstandingthatthisnewgenerationofvehiclesmaynotbeassafeastakingacommercialflightbetweensayNewYorkandLondon. TheofficiallinefromVirginGalacticaasSirRichard’slatestventureismodestlynamedisthatthiscomingchangeinthelawmakesnopracticaldifferencetothefirm’splanssincetheydonotintendtoflyunlesstheycanmaketheirspacecraftassafeasaprivatejet.Butitmustsurelycomeassomesortofrelief.InanycaseWillWhitehorndirectorofcorporateaffairsatVirgin’sheadquartersinLondonandsoontobecomethepresidentofVirginGalacticasaysthatworkisunderwayonamockupoftheinteriorofanewspacecraftthatwillholdfivepassengers.50Virginhasalreadycommitted$20mtowardslicensingtheSpaceShipOnetechnologyfromMr.RutanandhisfinancialbackerPaulAllenasoftwarebillionaire. 47
[A]DrDanielStanleyanoceanographerhasfoundvolcanicshardsinEgyptthathebelievesarelinkedtotheexplosion.ComputersimulationsbyMikeRampinoaclimatemodelerfromNewYorkUniversityshowthattheresultingashcloudcouldhaveplungedtheareaintodarknessaswellasgeneratinglightningandhailtwoofthe10plagues. [B]Thecloudcouldhavealsoreducedtherainfallcausingadrought.IftheNilehadthenbeenpoisonedbytheeffectsoftheeruptionpollutioncouldhaveturneditredashappenedinarecentenvironmentaldisasterinAmerica.Thesamepollutioncouldhavedrivenmillionsoffrogsontothelandthesecondplague.Onlandthefrogswoulddieremovingtheonlyobstacletoanexplosionoffliesandlice—thethirdandfourthplagues.Thefliescouldhavetransmittedfataldiseasestocattlethefifthplagueandboilsandblisterstohumansthesixthplague. [C]MoseswhichwillbebroadcastinDecember2002willsuggestthatmuchoftheBiblestorycanheexplainedbyasinglenaturaldisasterahugevolcaniceruptionontheGreekislandofSantoriniinthe16thcenturyBC. [D]Thehour-longdocumentaryarguesthateventhestoryofthepartingoftheRedSeawhichallowedMosestoleadtheHebrewstosafetywhilethepursuingEgyptianarmywasdrownedmayhaveitsoriginsintheeruption.Itrepeatsthetheorythat"RedSea"isamistranslationoftheSeaofReedsamuchshallowerswamp. [E]TheprogrammetellsthestoryofhowMosesledtheHebrewsoutofEgyptafteraseriesofplagueshaddevastatedthecountry.Butitalsousesnewscientificresearchtoarguethatmanyoftheeventssurroundingtheexoduscouldhavebeentriggeredbytheeruptionwhichwouldhavebeenathousandtimesmorepowerfulthananuclearbomb. [F]ComputersimulationsshowthattheSantorinieruptioncouldhavetriggereda600ft-hightidalwavetravelingatabout400milesanhourwhichwouldhavebeen6fthighandahundredmileslongwhenitreachedtheEgyptiandelta.Suchaneventwouldhavebeenrememberedforgenerationsandmayhaveprovidedtheinspirationforthestory. [G]FreshevidencethattheBiblicalplaguesandthepartingoftheRedSeawerenaturaleventsratherthanmythsormiraclesistobepresentedinanewBBCdocumentary. Order: 45
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