- 問題詳情:某地為了城市發展,在現有的四個城市A、B、C、D附近新建機場E.試建立適當的直角座標系,寫出點A、B、C、D、E的座標.【回答】以A點作為座標原點,經過A點的水平線作為x軸,經過A的豎直線作為y軸,每個小方格的邊長作為單位長,建立平面直角座標系,A(0,0)B(8,2)C(8,7)D(5,6)E(1,8)知識點:座標方法...
- 23497
- 問題詳情:現給定以下器材:A.閃光照相機B.秒錶C.打點計時器 D.交流電源4~6V E.導線若干 F.紙帶G.複寫紙 H.鐵架臺I.遊標卡尺 J.重物 K.刻度尺 L.直徑1cm的鋼球 M.1m長細線 N.照相底片設計一個測當地重力加速度g的實驗方案: (1)從給定器材中選(填器材前面的字母) 作...
- 27104
- 問題詳情: 2015年4月25日14時11分,某國發生了8.1級地震,震中位於28.2°N、84.7°E.據此完成1﹣2題.1.下面四幅圖能正確表示本次地震震中位置的是()A.① B.② C.③ D.④2.結合全球六大板...
- 18894
- 問題詳情:在化學實驗時必須注意安全*作,避免意外傷害,下列實驗*作或事故處理中不正確的是( )E. 在點燃易燃氣體前,必須檢驗氣體的純度F. 在稀釋濃硫*時,應將濃硫*用玻璃棒引流慢慢注入水中G. 濃硫*有腐蝕*,沾到面板上,應用較多的水沖洗,再塗上碳***稀溶液H. 不得點燃添滿酒精的酒...
- 28879
- 問題詳情:一絕緣光滑半圓環軌道放在豎直向下的勻強電場中,場強為E.在與環心等高處放有一質量為m、帶電+q的小球,由靜止開始沿軌道運動,下述說法正確的是()A.小球經過環的最低點時速度最大B.小球在運動過程中機械能守恆C.小球經過環的最低點時對軌道壓力為(mg+qE)D.小球經過環的最低點...
- 12383
- 問題詳情: E-mails,though_________exposedtomisleadinginformation,areconsideredfarmoreconvenientthantraditionalletters.A.occasionallyB.especiallyC.originallyD.naturally【回答】A知識點:副詞題型:選擇題...
- 11939
- 問題詳情:—Howdoyouspellyourname,please?— A.P-E-T-E-R,Peter. B.ThisisPeter.C.I'mPeter. D.YoucancallmePeter.【回答】A知識點:口語應用題型:選擇題...
- 10359
- 問題詳情: Withthedevelopmentofmodernsociety,E-mailaswellastelephones ________animportantpartindailycommunication. A.haveplayed B.isplaying C.areplaying D.played【回答】B知識點:主謂一致題型:選擇題...
- 19179
- 問題詳情:LiuYiting manyotherstudentswhostudyabroad English nativespeakers.A.asgoodas,speak,asgoodas B.aswellas,speaks,asgoodasC.aswellas,speaks,aswellas D.aswellas,speak,aswellas【回答】C 知...
- 24558
- 問題詳情:Recently,e-booksalesarefallingwhilesalesofpaperbooksaregrowing—anditismainlybecauseoftheyoungerpeople.Morethan360millionbooksweresoldintheUKin2016—a2%jumpinayearthatsawUKbuyersspendanextra6%onbooksinprintande-bookformats,accordingtofindings...
- 15273
- 問題詳情:已知函式f(x)=x·lnx(e為無理數,e≈2.718).(1)求函式f(x)在點(e,f(e))處的切線方程;(2)設實數a>,求函式f(x)在[a,2a]上的最小值.【回答】 (1)∵f(x)=x·lnx,∴x>0,f′(x)=lnx+1,∵f(e)=e,f′(e)=2,∴y=f(x)在(e,f(e))處的切線方程為y=2(x-e)+e,即y=2x-e.(2)∵f′(x)=lnx+1,令f′(x)=0,得x=,當x∈...
- 24021
- 問題詳情:Peopleinfloodedareassufferedalot,withoutdrinkingwater,electricityand________foodsupply,sotheycontinuedtofleethetown.A.suitable B.contentC.handy ...
- 9560
- 問題詳情:與130°E相對的經線是:( )A.50°E B.130°W C.230°E D.50°W【回答】 D知識點:地球和地球儀題型:選擇題...
- 13442
- 問題詳情:函式y=(ex+e-x)的導數是()A.(ex-e-x) B.(ex+e-x)C.ex-e-x D.ex+e-x【回答】A[y′=(ex+e-x)′=(ex-e-x).]知識點:圓錐曲線與方程題型:選擇題...
- 19254
- 問題詳情: E-mailEnglish_____usestwotypesofwords. A.mainly B.strongly C.gradually【回答】A知識點:副詞題型:選擇題...
- 8023
- 問題詳情: IstillremembermyfirstdayatschoolinLondonandIwashalf-excitedandhalf-frightened.OnmywaytoschoolIwonderedwhatsortofquestionstheotherboyswouldaskmeandpracticedalltheanswers:“Iamnineyearsold.IwasbornherebutIhaven’tlivedheresinceIwastwo.Iwasl...
- 31842
- 問題詳情:E-mailsystemsatthousandsofcompaniesandgovernmentofficesaroundtheworldwereattackedbyavirus(病毒)called“Melissa”thatdisguises(偽裝)itselfasan“importantmessage”fromafriend.Inspiteofaweekendofwarnings,morethan50000computersatabout100placesarou...
- 23906
- 問題詳情:---HowdoyouliketheconcertgivenbyF.L.R.? ---Exciting,______onepieceofthemusicwasn’tplayedquitewell. A.though B.because C.so D.and【回答】A知識點:連詞題...
- 8989
- 問題詳情:E-mail,aswellastelephones,________animportantpartindailycommunication.A.isplaying B.haveplayed C.areplaying D.play【回答】A知識點:現在進行時及其被動式題型:選擇題...
- 6981
- 問題詳情: *地(0°,90°E)、乙地(60°N,90°E)、*地(0°,40°E)、丁地(60°S,40°E)距本初子午線的距離由大到小的排列是 A.丁*乙* B.*乙*丁 C.**丁乙 D.*丁*乙【回答】B知識點:地球與地圖單元測試題型:選擇題...
- 12893
- 問題詳情: E-mail,aswellastelephones,____ animportantpartindailycommunication.A.isplaying B.haveplayed C.areplaying D.play 【回答】A知識點:主謂一致題型:選擇題...
- 14838
- 問題詳情: Withmoreforestsdestroyed,hugequantitiesofgoodearth eachyear. A.iswashingaway B.isbeingwashedaway C.arewashingaway D.arebeingwashedaway【回答】D知識點:現在進行時及其被動式題型:選擇題...
- 26372
- 問題詳情:設U={a,b,c,d,e},A={b,c,d},B={b,e},則等於A.{e} B.{a,b,e} C.{a,b,c,d,e} D.【回答】B知識點:*與函式的概念題型:選擇題...
- 32956
- 問題詳情:已知f(x)=ex-e-x,g(x)=ex+e-x(e=2.71828…)(1)求[f(x)]2-[g(x)]2的值;(2)若f(x)f(y)=4,g(x)g(y)=8,求的值.【回答】解析(1)[f(x)]2-[g(x)]2=(ex-e-x)2-(ex+e-x)2=(e2x-2+e-2x)-(e2x+2+e-2x)=-4.(2)f(x)f(y)=(ex-e-x)(ey-e-y)=ex+y+e-x-y-ex-y-e-x+y=[ex+y+e-(x+y)]-[ex-y+e-(x-y)]=g(x+y)-g(x-y)∴g(x+y)-g(x-y)=4 ...
- 17482
- 問題詳情: Managingyourtimewellisanimportantelementofsuccess—especiallyifyou’reastudent.Ifyousetprioritiesthatfityourneedsandlifestyle,you'llhaveabetterchanceofachievingyourgoals. Herearesometipsfortakingcontrolofyourtimeandorganizingy...
- 28431