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若方程x2﹣2x﹣4＝0的两个实数根为α，β，则α2+β2的值为（ ）
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一元二次方程x2﹣2x﹣1=0的根的情况为
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有两个不相等的实数根
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若αβ为方程2x2﹣5x﹣1=0的两个实数根则2α2+3αβ+5β的值为
﹣13
12
14
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若关于x的方程2x2+x﹣a=0有两个不相等的实数根则实数a的取值范围是.
已知关于x的方程x2﹣4mx+4m2﹣9=0.1求证此方程有两个不相等的实数根2设此方程的两个根分别
一元二次方程x2﹣2x﹣1=0的根的情况为
有两个相等的实数根
有两个不相等的实数根
只有一个实数根
没有实数根
已知αβ是方程x2﹣2x﹣4=0的两个实数根则α3+8β+6的值为
﹣1
2
22
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已知关于x的一元二次方程x2－x＋m＝0有两个不相等的实数根.1求实数m的取值范围2若方程的两个实数
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关于x的方程x2+2x﹣m=0有两个相等的实数根则m=
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方程x2﹣2x﹣4=0的根的情况
只有一个实数根
有两个不相等的实数根
有两个相等的实数根
没有实数根
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有两个不相等的实数根
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30分Whenlwasthreeyearsoldmyparentsdiscoveredlwastotallydeaf.After41withmanyeducationalexpertstheymadea42thatwouldforeverchangemyfuture.Insteadofsendingmetoaprivateschoolforthe43theydecidedtomainstreamme.Allofmy44andteacherswouldhavenormalhearing. SinceIstartedgoingthere1was45bytheotherkidsbecauseofmyhearingaidandthewayI46.Iexperiencedgreatanxietythroughouttheschool.Inadditiontotheproblemsof47withtheotherstudents1als048withmostofmyschoolwork.Theteachersdidn'tshowmuchinterestinanyofmyrareachievements.49Mrs.Jordanmy5thgradeteacherchangedallofthatwitha50three﹣wordphrase.Onemorningsheaskedtheclassaquestion.151herlipsandimmediatelyraisedmyhand.lcouldn'tbelieveit﹣foronceIknewtheanswer.Itookadeepbreathand52answeredherquestion. 1willneverforgetwhathappenednext.Herresponse53a110fus.Mrs.Jordanenthusiasticallyturnedher54inafullcircleuntilitpointeddirectlyatme.Withsparklingeyesanda55smileshecriedTHAT'SRIGHTSTEPHEN! Forthefirsttimeinmyyounglife1wasaninstantstar.Myheart56withPrideIsatalittle57inmychairandmyconfidenceincreasedlike58before.Asimplethree﹣wordphrasetotally59myyounglife.THAT'SRIGHTSTEPHEN!Fromthenonmygradesimproveddramatically.Mypopularityamongmypeersincreasedandmyoutlookonlifedidacomplete60. 41.A.dealing B.experimenting C.consulting D.comparing 42.A.decision B.survey C.mistake D.comment 43.A.blind B.deaf C.rich D.young 44.A.friends B.relatives C.patients D.schoolmates 45.A.caredfor B.laughedat C.calledup D.spokenof 46.A.learned B.walked C.talked D.hoped 47.A.comingup B.fittingin C.puttingup D.keepingup 48.A.disagreed B.quarreled C.struggled D.improved 49.A.Even B.Or C.So D.But 50.A.simple B.regular C.strange D.modest 51.A.opened B.touched C.moved D.read 52.A.fortunately B.suddenly C.nervously D.naturally 53.A.surprised B.delighted C.confused D.frightened 54.A.leg B.finger C.ear D.nail 55.A.slight B.wide C.false D.faint 56.A.burst B.broke C.filled D.hit 57.A.quieter B.deeper C.taller D.lighter 58.A.ever B.never C.past D.some 59.A.reflected B.discovered C.introduced D.transformed 60.A.attempt B.delay C.battle D.turnabout
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10分PositiveThinkingCanTransformYourHealth Ouremotional情感worldhasaremarkablepowertodeterminenotonlyourmentalhealthbutalsoourphysicalwell﹣being.Andagrowingbodyofresearchinpsychologymedicineandpublichealthisdisplayingthehealthbenefitofpositiveemotionsandtheireffectonphysicalhealth.36. 1.Optimismmayprotecttheheart. Accordingtoa2012reviewofliteratureanumberofstudieshaveshownthatpeoplewithoptimisticpersonalitiesareatareducedriskoftheheartattack.37suchasimprovedimmunesystemfunctionandincreasedlifespan. 2.Compassionandcareforotherscanimprovenervefunction. Compassionalovingconcernforthewell﹣beingofotherscanmakeusfeelpositiveandmayimproveourphysicalhealth. PositivepsychologistBarbarahasconductedresearchontheeffectsoflovingkindnessmeditation沉思atraditionalreligiouspracticethatinvolvesmeditatingonloveandextendingcompassiontooneselfandothers.38whichextendsfromthebraintothehearthelpingtoregulateemotionsaswellasbodilysystems 3.39. Likeoptimismanattitudeofgratitudeappreciationandfeelingofthankfulnessfortheblessingsonehasinlifecarriessignificantmentalandphysicalhealthbenefits.Gratefulnesslikeoptimismhasbeenlinkedwithimprovedimmunehealthandhasalsobeenshowntoimprovesleepquality. 4.Self﹣compassionimproveshealth﹣relatedbehaviors. 40.A2013studyfoundthatself﹣compassionatepeoplesoughtmedicalattentionsoonerthanpeoplewhowerelackinginself﹣compassion.Self﹣compassionatepeoplealsotendedtobelessdepressed. A.Optimism'sbenefitsforphysicalhealthalsoextendbeyondhearthealth B.Therearemanykindsofmethodstomakeusfeelpositive C.Herearefourpositiveemotionstoimprovephysicalhealthandpreventdisease D.Researchersfindthepracticecanhaveapositiveimpactonthenerve E.Peoplewhocultivatekindnesstowardsthemselvesarealsokindertotheirbodies F.Gratitudemayalsobenefithearthealthandimmunesystemfunction G.Thosewhoarekindtoothersareeasiertofeelrelaxed.
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