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过抛物线y2＝4x焦点F的直线交抛物线于A、B两点，交其准线于点C，且A、C位于x轴同侧，若|AC|＝2|AF|，则|BF|等于（ ）
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高二下学期数学《》真题及答案
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过抛物线y2＝4x的焦点F.的直线交该抛物线于A.B.两点.若|AF|＝3则|BF|＝_______
过抛物线y2=4x的焦点且斜率为1的直线交该抛物线于A.B.两点则|AB|=______.
若抛物线y2＝4x的焦点为F.过F.且斜率为1的直线交抛物线于A.B.两点动点P.在曲线y2＝－4x
已知抛物线ωy2=axa＞0上一点P.t2到焦点F.的距离为2tⅠ求抛物线ω的方程Ⅱ如图已知点D.的
过抛物线y2=4x的焦点F的直线交该抛物线于AB两点若|AF|=3则|BF|=.
设抛物线的顶点在坐标原点焦点F.在y轴正半轴上过点F.的直线交抛物线于A.B.两点线段AB的长是8A
已知过抛物线y2＝4x的焦点F.的直线交该抛物线于A.B.两点|AF|＝2则|BF|＝______.
过抛物线y2=4x的焦点F.的直线交该抛物线于A.B两点.若|AF|=3则|BF|=.
已知抛物线y2＝2pxp＞0过其焦点且斜率为1的直线交抛物线于
，
两点，若线段AB的中点的纵坐标为2，则该抛物线的准线方程为( ) A.x＝1B.x＝－1
x＝2
x＝－2
设F.为抛物线C.y2=4x的焦点过点P.﹣10的直线l交抛物线C.于两点A.B.点Q.为线段AB的
已知过抛物线y2=4x的焦点F.的直线交该抛物线于A.B.两点|AF|=2则|BF|=.
过抛物线y2＝4x焦点的直线交抛物线于
，
两点，若|AB|＝10，则AB的中点到y轴的距离等于( ) A.1B.2
3
4
过抛物线y2=4x的焦点作直线l交抛物线于A.B.两点若线段AB中点的横坐标为3则|AB|等于.
过抛物线y2=4x的焦点作直线l交抛物线于
B.两点，若线段AB中点的横坐标为3，则|AB|等于（ ） A.10
8
6
4
过抛物线y2=4x焦点的直线交抛物线于A.B.两点已知|AB|=8O.为坐标原点则△OAB的重心的横
过抛物线Cy2=2pxp＞0的焦点F的直线交抛物线于AB两点且AB两点的纵坐标之积为﹣4.1求抛物线
过抛物线C.y2＝4x的焦点F.作直线l交抛物线C.于A.B.两点若A.到抛物线的准线的距离为4则|
已知抛物线y2=2pxp>0过其焦点且斜率为1的直线交抛物线于
B.两点,若线段AB的中点的纵坐标为2,则该抛物线的准线方程为( ) A.x=1
x=-1
x=2
x=-2
过抛物线y2=4x的焦点作直线交抛物线于
（x1, y1）
（x2, y2）两点，如果
=6，那么
＝ （ ） （A.）6 （B.）8 （
）9 （
）10
过抛物线x2＝4y的焦点F.作直线l交抛物线于A.B.两点则弦AB的中点M.的轨迹方程是______
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10分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.错误涉及一个单词的增加删除或修改. 增加:在缺词处加一个漏词符号∧并在其下面写出该加的词. 删除:把多余的间用斜线\划掉. 修改:在错的词下画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处多若从第11处起不计分. ThismorningIwassurfingtheInternetinmybedroomtolookforsomeinformationsformystudy.SuddenlymymotherwasturnedupandshoutedatmethoughtthatIwasplayingacomputergame.Iwasveryangryandarguewithher.Afterthatmyfathercriticized批评meformyrudebehavior.IfeltupsetandhoweverIturnedadeafeartohim.Mymotherwasreallyhurtbuthestilltriedtoforgiveme.NowIfeelratherregretful.MyparentsaresoconcernedonmebutIhurtthem.Iwillbegformymother'sforgive.IthinkIoughtrespectmyparentswhateverhappensinsteadofjustthinkingofmyselfandlosemytemper脾气allthetime.
10分Naturedoesnothurryyeteverythingisaccomplished. ﹣﹣﹣LaoTzu Ifyouareinacitywhereeveryonerushesrealizethatyoudon'thavetobelikeeveryoneelse.Youcanbedifferent.Youcanwalkinsteadofdrivinginrushhourtraffic.YoucanbeonyouriPhoneorBlackberrylessanddisconnectedsometimes.Yourenvironmentdoesn'tcontrolyourlife﹣﹣﹣youdo.I'mnotgoingtotellyouhowtogiveyouastep﹣by﹣stepguidetomovingslower.1 1.Doless. Cutbackonyourprojectsonyourtasklistonhowmuchyoutrytodoeachday.Focusnotonquantitybutonquality.2Savesmallerroutinetasksforlaterinthedaybutgiveyourselftimetofocus. 2.Havefewermeetings. 3Andtheyeatintoyourdayforcingyoutosqueezethethingsyoureallyneedtodointosmallwindowsandmakingyourush. 3.4 Whenyoudotheimportantthingswithfocuswithoutrushtherewillbethingsthatgetpushedbackandthatdon'tgetdone.Andyouneedtoaskyourself:hownecessaryarethesethingsWhatwouldhappenifIstoppeddoingthem 4.Practicemindfulness. Simplylearntoliveinthepresentratherthanthingssomuchaboutfutureorthepast.Whenyoueatfullyappreciateyourfood.Whenyouarewithsomeonebewiththemfully.Whenyouarewalkingappreciateyoursurroundingsnomatterwhereyouare. Trythesethingsout.Lifeisbetterwhenunrushed. 5 A.Starttoputofforcanceltheunnecessary. B.Meetingsareusuallyabigwasteoftime. C.Theworldlikelywon'tendifyoudon'tpassoneoftheexaminations. D.Butherearesomethingstoconsiderandperhapsadopt采纳iftheyworkforyourlife. E.Rememberthequote:ifnaturecangeteverythingdonewithoutrushingsocanyou. F.Pick2﹣3importantthings﹣﹣﹣orevenjustoneimportantthing﹣﹣﹣andworkonthosefirst. G.Giveyourselfmoretimetogetreadyandgetthere.
25分阅读下面短文根据其内容写一篇60词左右的内容概要.Oneofthetoughestthingsaboutbeingahighschoolstudentisthatyouneverseemtogetenoughsleepatnightwhichoftenleavesyounoddingoffduringclasses.Spendingeitherlessthansixormorethanninehoursinsleepingputsyourhealthatrisk.Apopularsolutiontoalackofsleepatnightistotakea'powernap小睡'duringthedaybutdoesthisworkGenerallyspeakingitcanbebeneficial.Researchshowsthatanapintheday﹣﹣﹣evenabriefoneasshortastenminutes﹣﹣﹣canclearyourmindandleaveyouwithincreasedenergyandimprovedproductivity.Herearesomethingsyouneedtoknowtonapcorrectly.Tostartwitheverytimeyoudozeoff打瞌睡duringthedaydoesnotcountasa'powernap'.Thebesttimetotakeapowernapisinthemid﹣afternoonwhenyourenergyleveltendstodecrease.Trytoavoidnapsafter4pmforsleepingtoolateinthedaycanmakeithardertofallasleepatnight.HowlongshouldapowernapbeGrabbing10﹣30minutesofrestisusuallybestforamiddle﹣of﹣the﹣daynap.Youarenotreallygettingestablishedsleepifyounodoffforonlyfiveminutes.Howevernappingmorethan40minutescanleaveyoufeelingsleepierthanwhenyoustartmeaningyou'llhavetogothroughthewholewaking﹣upprocessafteryougointothedeeperstageofsleep.Howeverasrefreshingasitmightbeifyouaregettingenoughsleepatnighttakingapowernapisn'tsuchawisechoice.Thereasonisthatsleepingduringthedaycaninterferewith妨碍yourbody'sbiorhythms生理节奏.Thebraingetsusedtogoingtobedatroughlythesametimeeachnightandgettingupatthesametimeeachdayandyoudon'twanttodisturbthisroutine.
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8分In1971ayoungmanwhogrewupverypoorwastravellingacrossthecountrytryingtomakeanewstartforhimself.Alongthewayhehadcompletelyrunoutof用光moneyandwasforcedtospendthenightinhiscar.Thiscontinueduntilonemorningafteraweekofsleepinginhiscarhewalkednervouslyintoarestaurantandorderedabigbreakfast. Aftereatinghisfirstgoodmealinweekshefoundhimselflyingtothewaitertellinghimhehadlosthiswallet.Thewaiterwhowasalsotheownerwalkedbehindthechairwheretheyoungmanhadbeensitting.Hebentdownandcameupwitha﹩20billthatlookedasifithadfallenonthefloorandsaidSonyoumusthavedroppedthistheownersaid.Theyoungmancouldn'tbelievehisluck!Hequicklypaidforthebreakfastleftatipboughtgaswiththechangeandheadedwest. Onthewayoutoftownhebegantounderstandwhattheownerdid.Maybenobodydroppedthemoneyatall.MaybethatfellowjustknewIwasintroubleandhehelpedmeinawaythatdidn'tembarrassme.SoIjustmadeapromisetohelpotherpeopleifIcan. Laterheworkedveryhardandbecamearichman.NowhelivesnearKansasCity.Eachyearhegivesawaythousandsofdollars.HeisknownastheSecretSantabecauseatChristmastimeeachyearhepersonallyhandsmoneyouttothoseonthestreetandatrestaurants.Lastyearhegavemorethan﹩50000awayinKansasCity. 1Theyoungmanwastravellingacrossthecountryin1971to. A.lookforagoodrestaurant B.improvehislife C.showhisnewcartoothers D.handoutdollars 2Theunderlinesentenceimpliesthattheyoungmangottoknowthat. A.theownerhelpedhiminawaythatdidn'thurthisfeeling B.Itwasveryhonestoftheownertoreturnhismoney C.Itwasveryluckyofhimtogethislostmoneyback. D.anotherpersonwhohadbreakfastintherestaurantlostthemoney 3Fromtheendofthepassagewecanlearnthat. A.theownerwaspaidbackthemoney B.themanwasnotsuccessfulintheend C.themandidcarryouthispromise D.Santagivethemanmoneyeachyear 4Themessageofthestoryis. A.Doingisbetterthansaying B.Wherethereisawillthereisaway C.Hewhotravelsfarknowsmuch D.Givelovewingsanditmayflyhigher
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在“研究匀变速直线运动的规律”的实验中某同学获得的一条纸带如图所示． 1已知打点计时器电源频率为50Hz则纸带上打相邻两点的时间间隔为． 2ABCDEFG是纸带上7个计数点每两个相邻计数点间有四个点没有画出从图中读出AB两点间距x＝m 3C点对应的速度是m/s小车运动的加速度为m/s2．计算结果保留二位有效数字． 4若实验后发现实际所用交流电的频率高于50hz则上述计算结果与实际值相比是．填“偏大”“偏小”还是“不变”
如图所示倾角为θ＝37°足够长的斜面体固定在水平地面上小木块在沿斜面向上的恒定外力F作用下从斜面上的A点由静止开始向上作匀加速运动前进了4.0m抵达B点时速度为8m/s．已知木块与斜面间的动摩擦因数μ＝0.5木块质量m＝1kg．g＝10m/s2取sin37°＝0.6cos37°＝0.8． 1木块所受的加速度多大 2木块到外力F多大
7.5分Theanswertoprotectingandsavingmarine海洋wildlifecanstartwithcuttingbackonsomethingAmericansuseeveryday﹣plasticdrinkingstraws.ActorAdrienGrenierbestknownforplayingVincentChaseinthe2015movieEntouragelaunchedacampaigntoreducetheamountofsingle﹣useplasticusageinthiscountryinordertoprotectandsavemarinewildlifeandtheenvironment.Plasticdrinkingstrawsareamongmanymanysingle﹣useplasticproductscontributingtotheshockinglossofmarinelifebutthey'reagreatplacetostartbecausethey'resomethingAmericansareusingbythehundredsofmillionswithoutanyawarenessthatthey'resodamaging. AccordingtoEcocycleaninternationalenvironmentalorganizationAmericansusemorethan500millionstrawsdailywhichareenoughtofill127schoolbuseseachdayandtheycan'tberecycled.That meansplasticstrawsendupinlandfillsoroceanswherefishandothermarinewildlifemistakethesmallbitsforfoodandswallowthem.AfterseeingaphotoofawhalebeachedontheshorewithabellyfullofplasticGrenierfelttheinspirationtolaunchtheLonelyWhaleFoundationhopingtoinspireandeducateothersonthechallengesfacingmarinelife. AlongwithstoppingtheuseofstrawsGrenierhopestoeducateconsumersonthedangersofothersingle﹣useplasticitemssuchasgrocerybagsandwaterbottles.WhilemanyAmericansusetheseplasticproductsintheirdailylifetherearemoresustainablealternativesthatcanhelpprotecttheenvironmentEcocyclerecommendstheuseofstrawsmadefromstainlesssteelglassandevenbambooinsteadofplastic.Youcanbuyanumberoftheseenvironmentallyfriendlystrawsonlineandinstores. 1WhatistheprimarypurposeoftheLonelyWhaleFoundation A.Toadvocateagreenlifestyle. B.TopromoteGrenierslatestmovie. C.Toencouragepeopletoprotectoceanlife. D.Tosavepreciousnaturalresources. 2WhatcausedGreniertostarttheLonelyWhaleFoundation A.Apictureofadeadwhale. B.Plasticstrawsinlandfills. C.Theseveredamagedonetothesea. D.Thedisappearanceofsomespeciesunderthesea. 3Ecocycleadvisespeopletousestrawsthatare. A.easytorecycle B.harmlesstotheenvironment C.specialtomarinelife D.convenienttouse
6分Myson.ThephrasefeltdifficultandstrangethefirsttimeIsaiditandIhadtopracticeitathousandtimes.Istartedsayingthewordstomyselfthedaywhentheultrasound超声波toldmewewerehavingababy. Finallymysonwasborn. Thenursecameoutofthedeliveryroomholdingatinyhowlinghumanbeingwrappedinawhitesheethissmallhandsanddelicatefingersshakingnervously. BabySanchezsheaskedlookingattheroomfullofexpectantfathers. Istoodupholdingmybreath. Sheshowedmemybaby.MysonIwhispered.Thelittleguyscreamedwaaaaaaaaaah. ButinmyheartIheardhimcryoutDaaaaaaad!Idon'tcareifeveryoneintheroomwillsaytheydidn'thearmybabysaythat.IcalledhimMysonandhecalledmeDadandthat'sthat. PeopleaskmeWhatdidIfeelatthatmomentIcan'tevenbegintoanswer.I'mawriteryetItryhardtofindtherightwords.Joyfulisn'tpowerfulenough.Bliss狂喜isnotsweetenough.Peacefulisn'tcalmenough.Happyisn'ttenseenough. AftermysonwastakenawaytothenurseryIsatdownandshutmyeyes.Buttearsescapedthemaway.Thensuddenlymy80﹣year﹣oldfatherenteredandweembraced拥抱. DadIwhispered. Mysonmyheartheardhimsaying. Suddenlythepast33yearsfoldedintothepresentandIwasnowthebabybundledinwhitewithmyfatherstandingoverme. MysonIimaginedhimsaying. Daaaaaaaaaad!Icriedmylittlelungsout. AtthatpointIknewIwasgoingtobeagreatfather.Theoldmaninfrontofmeseemedtoagree.Hesmiledandwewalkedoutoftheroominsearchofthelittlehumanbeingthatwouldchangeourlivesforever. 1Theauthorcouldn'ttellhowhefeltatthemomentbecause. A.hewasawriter B.hewastooexcited C.hewastoonervous D.it'safeelingtoohardtoexpress 2WecanlearnthefollowingfromthepassageEXCEPTthat. A.theauthorgothisfirstbaby B.heprobablyhadalungdisease C.theauthordidn'treallyhearDaaaaadfromhisbaby D.thebabywouldchangetheauthor'slife 3Whywasthewritersurehewasgoingtobeagreatfather A.Becausehissonissogifted. B.Becausehehadmuchexperienceinbringingupchildren. C.Becausehisfatherpromisedtohelphim. D.Becausehisfatherhadalreadysethimagoodexample.
30分IwasshoppinginasupermarketlastnightwhenIsawahomelesswomanwithatrolley手推车fullofallherthings.Shewassittinginsidetokeep1.Iwentuptoherandtriedtogiveher2forsomethingtoeat.Shewouldn't3it.IsaidIwantedtohelpher4shesaidthatifenoughmoneywasgiventoherthatdayandshehadmoneyonherotherhomelesspeoplewould5itfromherwhilesheslept. I6thatIwantedtohelpherandaskedifIcouldbuyhersomethingwarm.7shesaidno.Shethankedmeandsaidhow8shewasthatIhadspokentoherandoffered9.WeintroducedourselvesandshesaidthatwhenIsawherthenexttimeshewould10accepthelp. Iwalkedoutintothecoldwinter11andgavethemoneytoahomelessmanwhowasfreezing.Iaskedhimhisname12IalwayswanttoknowandItoldhimmine.HappearedtohavehadadrinkingordrugproblembutIwas13thatheacceptedmyhelp. Ihadthis14thatstayedwithme.IfeltthatIhadbeeninthepresenceofsomeonereallyspecialearlier.Ialways15whatitwouldbeliketobeinahomelessperson'sshoesIknowhow16IamandhowgratefulIamforwhatI17inmylife. Ilearnedavaluable18fromtheladyImet:Notall19peoplewilltakemoneyorhelpiftheyfeelenoughhasbeengiventothemthatday.Shewasgratefulfortheday.IwillmakesureI20heragain. 1Acalm B.warm C.healthy D.energetic 2A.time B.freedom C.money D.choice 3A.take B.make C.eat D.receive 4A.and B.or C.so D.but 5A.spend B.steal C.find D.hide 6A.agreed B.wondered C.apologized D.explained 7A.Again B.Besides C.Instead D.Thus 8A.proud B.curious C.regretful D.grateful 9A.help B.food C.strength D.advice 10A.generously B.willingly C.slightly D.politely 11A.morning B.noon C.afternoon D.night 12A.unless B.when C.because D.though 13A.glad B.sure C.astonished D.puzzled 14A.hope B.feeling C.belief D.courage 15A.expect B.believe C.imagine D.remember 16A.lucky B.unique C.serious D.confident 17A.observe B.own C.support D.respect 18A.fact B.quality C.lesson D.subject 19A.lonely B.hungry C.helpless D.homeless 20A.call B.ask C.meet D.follow
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＝ （ ） （A.）6 （B.）8 （ ）9 （ ）10
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