炎德文化数学2024年普通高等学校招生全国统一考试考前演练一答案
18.(12分)解:(1)设等差数列{a}的公差为d.d>0,「S,=12a2=a606-02a1+d=4a+2=a+sa……2分整理得,5d2-2d-16=04分解得d=2减=号(舍).a1=d=2an=2n,n∈…6分(2)由(1)知,...
18.(12分)解:(1)设等差数列{a}的公差为d.d>0,「S,=12a2=a606-02a1+d=4a+2=a+sa……2分整理得,5d2-2d-16=04分解得d=2减=号(舍).a1=d=2an=2n,n∈…6分(2)由(1)知,...
设P(x,),A(x1,y),直线AP的方程为y=k(x-2)1分(同焦点坐标)代入双曲线方程x2-y2=2得(1-k2)x2+4k2x-4k2-2=04k2>01+k2≠0x+x=k2-14k2+2、1分(同渐近线方程),合计...
数学爱好者七年级同步训练下册(华师大版)。SHUXUE AIHAO ZHE8.(2021·杭州)以下是圆圆解不等式组12.(2021·十堰)定义:对于实数a,符号[a]2(1+x)>-1,①表示不大于a...
17.解:(1)设{an}的公差为d,因为a2=4,2a4-a5=7,所以2(4+2d)-(4+3d)=7,解得d=3,从而a1=1,1分所以m=3n—2.…3分设么的公比为6:因为么+价=8十.所以哈-会==8解得)=2。...
即y=(x+a+1)e·x+(a-x-ax)e,.6分同理f(x)在(x,f(x)处的切线方程为y=(x+a+1)e·x+(a-x-ax)e,(x+a+1)e=(x+a+1)e,且它们重合,所以.7分(a-x-axo)e"=(a-xi-ax)e",整理...
两分12分)每年的3月12日是植树节,某公司为了动员职工积极参加植树造林,在植树节期间开展植树有奖活动,设有甲、乙两个摸奖箱,每位植树者植树每满25棵获得一次...
最新中考模拟训练·数学参考答案.CG⊥AB,AG+CG,∠CAB=∠BCG=45°,.∠DAG=∠FCG=135.ED⊥CD,∠DCB=90°,.DE∥BC,∴·△DEA为等腰直角三角形,..DE=AD图1DE⊥CD,EF⊥BC,∠DCF=∠DCB...
Where is the man working nowA.In England.所第7段材料,回答第8至10婚B.In France.C.In America.thee eA.In a gym.3、64题)。B.In a swimming pool.Why does t...
40.What is cultural competence according to the passage?41.Why is cultural competence important for people in intercultural environment?42.Please deci...
7.D【详解】解:因为a+B=(a>0,B>0),>(t-)71-o+1)54所以0<a<0<B<年,所以0<me<10<mB<,中是,A【010门Atan(tantan=tn0)1-tan a tan B4所以tana+tanB=1-tanatanB,...
三,解答题(本大题共5小题,每小雕6分,共30分)3.(本赠共2小题,每小题3分g3)+-45-子(-)解赋15-子出52)化0,(11解-2a+*。4-审)Xt0)-02)小育才中学计划名开“城...
The studyok000 mem and women aged 6 whoInternal Medicine.aicpd43the UK Biobank,which houses indepth genetic and healthnbewenand 2010.The database incl...
又因为a1=1,所以2=4,所以,当n≥2时,{an}是以4为首项,2为公比的等比数列,所以an=4×2”-2=2”所以a.=2°,≥21,n=16分(2)因为bn=log2an,所以,当n=1时,b1=log2=lo...
18.(12分)已知一个盒子中有除颜色外其余完全相同的5个球,其中2个红球,3个白球现从盒子中不放回地随机摸取3次,每次摸取1个球.(1)求第二次摸出的球是红球的概率...
a解得AF=同理可得AE=2·6分sin(45+0)cos0∴Sg=dB4Rsin∠EAf=-da'cos0sin(45+0)22sim(20+45)+20e[045])当20=45时,S的最小值5-Da·10分221.(1)证明::BE=EF=FC=1,B...
所以数列{an}不是等比数列,以不存在.选择条件②,不存在!因为数列{Sn+1}是公比为3的等比数列,所以S2+1=3(S1+1),又S+s=4,得S,=2,所以S.十1=三×3133S,-×3-1,所...
【来源】自主作业本练习题【答案】D【解析】由题意,灯泡不亮包括四个开关都开,下边的2个都开且上边的2个中有一个开另一个闭,这三种情况是互斥的,每一种情况...
2直线1的斜率为长P习行,直线W的斜率为6r1-(4.53-1所以点M不在直线L上,因此L∥(故选A3.由kx=422=-2.设BC边上的高的斜率4-(-2)为,则=故选C4.由题意知a≠0,b≠0,...
0+24.1Alnx+lny有最大值4B.2有最小值3C.xy有最小值3D.w有最大值4【答案】BD【解析】9【分析】对于A,直接由基本不等式求得4,即可判断A:对于B,将y=3,x代入2+y24.1...
2023年高三摸底考试飞现有一张正方形剪纸,沿只过其一个顶点的一条直线将其剪开,得到2张纸片,再从中任选一张,沿只过其一个顶点的一条直线剪开,得到3张纸片,...
DIY:Home-made Beauty ProductsBy Cassia AlbinsonPaperback$18.33 Prime In Stock$9.71 used new (2 offers)The recipes for home-made beauty products in thi...
可学科网密组卷船7.在平面直角坐标系中,A(0,-2),B(0,2),平面中动点P满足条件PA+P8=m+4(m为常数,m且m>2),则点P的轨迹是()A.椭圆B.线段C.直线D.椭圆或线段&已灯...
5.like;best6.Which coat do you7.What did;see8.How many colours are thereIII.1.there's nothing wrong with2.Which one do you3.looks beautiful on you4.no...
四、解答题:本题共6小题,第17题10分,其它每题共70分.解答应写出文字说明、证明过程或演算步骤,17.已知直线l:mx一y+1一m=0和圆C:x+(y-1)5.(1)求证:对任意实...
much money,she'll be happy and emotionally satisfied. W:But she'll have bills to pay.It's going to be hard for her to lead a life on what an artist ma...
walking through Central Park on his way to work.On a path be- hind the Great Museum,he noticed a large newspaper sheet lying ahead.When he picked it u...
53.A.however B.therefore C.again D.thus 54.A.laughed B.nodded C.shook D.realized 55.A.know B.break C.hurry D.continue 56.A.felt B.judged C.recognized...
48.D ,根据上文的“As a blind person,Shifrin had never before been able to a Lego set on his own.”可知,Shifrin意识 到自己要帮助盲人儿童获得独立性,即可...
W:More haste,less speed.To have a walk outside may also work.Last year the school offered a stress management course.Have you been in contact with the...
our 1949 Ford out of the garage a few times to get used to the clutch(离合器)and gearshift(换挡杆). Finally,the day came for Daddy to give me a real l...