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若代数式有意义,则实数x的取值范围是 .
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若代数式在实数范围内有意义则x的取值范围是
x≥-3
x>3
x≥3
x≤3
若代数式有意义则实数x的取值范围是
x=0
x=3
x≠0
x≠3
若代数式在实数范围内有意义则x的取值范围是
x≥-3
x>3
x≥3
x≤3
若代数式有意义则实数x的取值范围是____________.
若代数式有意义则实数x的取值范围是
若代数式在实数范围内有意义则x的取值范围是_______
要使代数式有意义实数x的取值范围是____________.
若代数式在实数范围内有意义则x的取值范围是____________.
如果代数式有意义那么实数x的取值范围是.
若代数式在实数范围内有意义则x的取值范围为
x<-3
x≥-3
x>2
x≥-3,且x≠2
若代数式有意义则实数x的取值范围是__________.
代数式在实数范围内有意义则x的取值范围是
若代数式有意义则实数x的取值范围是=*.
代数式在实数范围内有意义则x的取值范围是
若代数式在实数范围内有意义则实数x的取值范围是
x≥﹣1
x>2
x≠2
x≥﹣1且x≠2
若代数式在实数范围内有意义则实数x的取值范围是
x<3
x>3
x≠3
x=3
代数式在实数范围内有意义则x的取值范围是.
写出一个只含字母x的代数式要求1要使此代数式有意义2字母x的取值范围为全体实数3此代数式的值恒为正数
若代数式在实数内范围有意义则x的取值范围为.
若代数式在实数范围内有意义则实数x的取值范围是
x<3
x>3
x≠3
x=3
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Neversaygoodbye WhenIwastenIwassuddenlyconfrontedwiththeseverepainofmovingfromtheonlyhomeIhadeverknown.Mywholelifebriefasitwashadbeenspentinthatbigoldhousedeeplyandthankfullytouchedbythelaughterandtearsoffourgenerations. WhenthefinaldaycameIrantotheheavenofthesmallbackporch走廊andsatalonetremblingastearswelledupfrommyheart.SuddenlyIfeltahandrestonmyshoulder.Ilookeduptoseemygrandfather.Itisn'teasyisitBilly?hesaidsoftlysittingdownonthestepsbesideme. GrandpaIrepliedthroughmytearsHowcanIeversaygoodbyetoyouandallmyfriends? Foramomenthejuststartedoffintotheappletrees.Goodbyeissuchasadwordhesaid.Itseemstoofinaltoocoldforfriendstouse.Weseemtohavesomanywaysofsayinggoodbyeandtheyallhaveonethingincommonsadness. Icontinuedtolookintohisface.Hegentlytookmyhandinhis.Comewithmemyfriendhewhispered. Wewalkedhandinhandtohisfavoriteplaceinthefrontyardwhereahugeredrosebushsatattractivelyalone. WhatdoyouseehereBilly?heasked. IlookedattheflowernotknowingwhattosayandthenansweredIseesomethingsoftandbeautifulGrandpa. Kneelinghepulledmeclose.Itisn'tjusttherosesthatarebeautifulBilly.It'sthatspecialplaceinyourheartthatmakesthemso. Hiseyesmetmineagain.BillyIplantedtheserosesalonglongtimeago﹣beforeyourmotherwasevenadream.Iputthemintothesoilthedaywhenmyfirstsonwasborn.Itwasmywayofsayingthank﹣youtoGod.Thatboy'snamewasBillyjustlikeyours.Iusedtowatchhimpickrosesforhismother. Isawmygrandfather'stears.Ihadneverseenhimcrybefore.Hisvoicebecamehoarse. Onedayaterriblewarcameandmysonlikesomanysonswentawaytofightagreatevil.HeandIwalkedtothetrainstationtogether﹣﹣﹣Threemonthslateratelegramcame.MysonhaddiedinsometinyvillageinItaly.AllIcouldthinkofwasthatthelastthingIsaidtohiminthislifewasgoodbye. Grandpaslowlystoodup.Don'teversaygoodbyeBilly.Don'tevergiveintothesadnessandtheloneliness.Iwantyoutorememberthejoyandthehappinessofthosetimeswhenyoufirstsaidhellotoafriend.Takethatspecialhelloandlockitawaywithinyou﹣inthatplaceinyourheartwheresummerisaregulartime.WhenyouandyourfriendsmustbepartedIwantyoutoreachdeepwithinyouandbringbackthatfirsthello. Ayearandhalflatermygrandfatherbecamegravelyill.Whenhereturnedfromseveralweeksinthehospitalhewantedhisbednexttothewindowwherehecouldseehisbelovedrosebush. ThefamilywassummonedandIreturnedtotheoldhouse.Itwasdecidedthattheoldestgrandchildrenwouldbeallowedtosaytheirgoodbyes.WhenitcametomyturnInotedhowtiredhelooked.Hiseyeswereclosedandbreathingwasslowandhard. Itookhishandasgentlyashehadoncetakenmine. HelloGrandpaIwhispered.Hiseyesslowlyopened. Hellomyfriendhesaidwithabriefsmile.HiseyesclosedagainandImovedon. Iwasstandingbyhisrosebushwhenanunclecametotellmethatmygrandfatherhaddied. RememberingGrandpa'swordsIreacheddeepwithinmeforthosespecialfeelingsthathadmadeupfriendship.SuddenlyandtrulyIknewwhathadmeantaboutneversayinggoodbye﹣refusetogiveintosadness. 1Theauthor'spurposeofwritingthispassageisto. A.conveyhissadnessandsorrowformovinghouse B.describethelaughterandtearsofthegenerationslivingtogether C.explaintherealmeaningofneversaygoodbye D.cherishthememoryofhisuncleandhisgrandfather 2Fromthelastparagraphwecaninferthat A.theauthor'sgrandfatherdied B.theauthordidn'tfeelsadabouthisgrandfather'sdeath C.theauthorhadadeepfriendshipwithhisgrandfatherratherthanlove D.theauthor'sgrandfatherlivesinhisheartforever 3ThefollowingstatementsbasedonthepassageareallrightEXCEPT A.theauthor'sunclehadbeeninthewarforlessthanhalfayear B.theauthorreturnedtotheoldhouseinordertolookafterhisgrandfather C.theauthor'sgrandfatherplantedtheroseswhentheauthor'sgrandmotherhadachild. D.theauthor'soldhousewasfilledwithlaughterandtears 4Whydidtheauthor'sgrandfathercrywhenwalkingwithhimintheyard? A.Hewassatisfiedwiththewholehappyfamily. B.Hewascontentwiththebloomingredroses. C.Therosesremindedhimofhisfirstsonwhodiedinthewar. D.Therosesbroughthimbacktothemomentwhensayinggoodbyetohisfirstson. 5Theunderlinedwordgravelyisclosestinmeaningto. A.gently B.seriously C.gracefully D.uncomfortably 6Whichofthefollowingcanbestdescribetheauthor'sgrandfatheraccordingtothepassage? A.Kindandstrong﹣willed B.Cautiousandenthusiastic C.Considerateandscholarly D.Humorousandsincere
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Mygrandmotherwasalwaysencouragingmetosetgoalsandworkhardtoachievethem.Shewouldtellmenottobeafollowerandnottoset1onwhatIcouldachieve.She2believedthattherewerenolimitsthatyoucould3whateveryouwanted.Iwouldneverforgetthefollowingstorythatsheoncetoldme.Afarmerwonfirst4atthecountryfairforhishugeradish小萝卜thatwastheexactshapeand5ofamilkbottle.Manywere6astohowthefarmerwasabletogrowthisradishthatwastheexactshapeofamilkbottle.7onegentlemanwentuptothefarmerandaskedthequestion.Thefarmerreplied'Itwas8.IgottheseedgrowingandthenIputitintothemilkbottle.Ithad9elsetogo.'Youcanusethisstoryasananalogy比喻tolife﹣ourlivesare10bythekindofsurroundingsweplaceourselvesinthepeoplethatweallowto11usandthegoalswegiveourselves.Ifweonly12andtakenoactionthenwegetnofurther.Butifwe13setagoalandtakeactionthenourlifetakesa14shape.Goalsandactionscanhelpusaccomplishmoreinayearthanwhatsomepeoplewillaccomplishinalifetime.Toprovethis15readthebiographiesof16peopleandyouwillseethatgoalsandactions17playedabigroleintheirsuccess.Rememberthe18ofMaryKayAshwhosaid'Don'tlimityourself.Manypeoplelimitthemselvestowhattheythinktheycando.Youcango19yourmindletsyou.Whatyoubelieverememberyoucanachieve.'Insummarydon'tputyourselfinabottleinotherwordsmoveoutofwhatis20andsecureifyouwanttomoveforward.1A.expectations B.rules C.limits D.lines2A.truly B.naturally C.tightly D.partly3A.win B.grasp C.realize D.achieve4A.price B.prize C.position D.award5A.size B.length C.weight D.height6A.doubtful B.worried C.anxious D.curious7A.Immediately B.Gradually C.Finally D.Actually8A.strange B.easy C.funny D.secret9A.nowhere B.everywhere C.somewhere D.anywhere10A.shaped B.formed C.controlled D.improved11A.understand B.help C.influence D.contact12A.dream B.refuse C.doubt D.change13A.struggle B.refuse C.continue D.plan14A.beautiful B.different C.solid D.clear15A.truth B.lesson C.point D.evidence16A.successful B.brave C.friendly D.careful17A.asusual B.aboveall C.atall D.infact18A.case B.wisdom C.thought D.speech19A.asif B.incase C.asfaras D.aslongas20A.comfortable B.valuable C.ordinary D.boring
根据如图所示四个实验按要求填空. 1在实验室用A装置制取二氧化碳所用药品为指出用该装置制取二氧化碳气体的一个明显错误的是. 2B实验的试管1中产生的气体是写化学式由此实验得出水是由组成的. 3C实验中将镁条在空气中点燃后再放入充满CO2的集气瓶中发现镁条继续激烈燃烧发出白光放热产生一种白色固体和一种黑色固体已知该反应为置换反应则反应的化学方程式为. 4用D装置干燥并收集某气体该气体可能是写化学式填一种即可.
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高一上学期化学
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教案备课库