alevel数学试卷答案[推荐]
alevel 数学考试真题 艾德思9709_s02_qp_1

x x intersecting at O and P. Find
(i) the coordinates of P,
[1]
(ii) the area of the shaded region.
[5]
4 A progression has a first term of 12 and a fifth term of 18.
[3]
(iii) find this stationary value and determine whether it is a maximum or a minimum.
[3]
dy
12
9
A curve is such that dx
(2x 1)2 and P (1, 5) is a point on the curve.
B'
4
O'
A'
=
M
12
=
C
k
j
B
O
i
A
The diagram shows a solid cylinder standing on a horizontal circular base, centre O and radius 4 units. The line BA is a diameter and the radius OC is at 90Æ to OA. Points O¼, A¼, B¼ and C¼ lie on the upper surface of the cylinder such that OO¼, AA¼, BB¼ and CC¼ are all vertical and of length 12 units. The mid-point of BB¼ is M.
alevel试卷数学真题考试

alevel试卷数学真题考试ALEVEL 数学试卷考试编号:MAT-ALEVEL-2024考试时间:2小时30分钟注意事项:1. 请在答题纸上作答。
2. 所有计算题请写出详细的解题步骤。
3. 选择题部分请在答题纸上标注清楚选项。
4. 考试结束后,请将试卷和答题纸一并交回。
一、选择题(每题2分,共20分)1. 下列哪个选项是方程 \( x^2 - 5x + 6 = 0 \) 的解?A. \( x = 2 \)B. \( x = 3 \)C. \( x = 1 \)D. \( x = 4 \)2. 函数 \( f(x) = 3x^2 - 2x + 1 \) 的导数是:A. \( 6x - 2 \)B. \( 6x^2 - 2 \)C. \( 6x + 1 \)D. \( 6x - 4 \)3. 圆 \( (x-3)^2 + (y-4)^2 = 25 \) 的半径是:A. 5B. 10C. 20D. 254. 以下哪个级数是收敛的?A. \( \sum_{n=1}^{\infty} \frac{1}{n^2} \)B. \( \sum_{n=1}^{\infty} \frac{1}{n} \)C. \( \sum_{n=1}^{\infty} n \)D. \( \sum_{n=1}^{\infty} (-1)^n \)5. 矩阵 \( A = \begin{bmatrix} 1 & 2 \\ 3 & 4 \end{bmatrix} \) 的行列式是:A. -1B. 1C. 2D. 76. 以下哪个是二项式定理 \( (x + y)^n \) 的展开式中的通项公式?A. \( \binom{n}{k} x^k y^{n-k} \)B. \( \binom{k}{n} x^n y^{k-n} \)C. \( \binom{n}{n-k} x^k y^{n-k} \)D. \( \binom{k}{k} x^n y^{n-k} \)7. 以下哪个是正弦函数 \( y = \sin x \) 的周期?A. \( 2\pi \)B. \( \pi \)C. \( 4\pi \)D. \( \frac{\pi}{2} \)8. 以下哪个是复数 \( z = 3 + 4i \) 的模?A. 5B. 7C. 25D. 509. 以下哪个是双曲线 \( x^2 - y^2 = 1 \) 的渐近线方程?A. \( x = \pm 1 \)B. \( y = \pm x \)C. \( y = \pm \frac{1}{\sqrt{2}}x \)D. \( y = \pm \sqrt{2}x \)10. 以下哪个是微分方程 \( \frac{dy}{dx} = 3x^2 - 2y \) 的解?A. \( y = x^3 - 2x \)B. \( y = x^3 + 2x \)C. \( y = x^3 - 2x^2 \)D. \( y = x^3 + 2x^2 \)二、简答题(每题10分,共30分)11. 解线性方程组:\[\begin{cases}x + 2y = 5 \\3x - y = 1\end{cases}\]12. 证明不等式 \( \frac{1}{n+1} + \frac{1}{n+2} + \ldots + \frac{1}{2n} > \frac{1}{2} \) 对所有正整数 \( n \) 成立。
alevel数学统计S1答案

alevel数学统计S1答案1、20.如图,OC是∠AOB的平分线,OD是∠BOC的平分线,那么下列各式中正确的是()[单选题] *21.A.∠COD=∠AOBB.∠AOD=∠AOBC.∠BOD=∠AODD.∠BOC=∠AOD(正确答案)2、5、若关于x的一元二次方程(a-1)x2+x+a2-1=0的一个根是0,则a的值是()[单选题] *A、1B、-1(正确答案)C 、1或-1D、23、下列说法中,正确的是[单选题] *A.一个有理数不是正数就是负数(正确答案)B.正分数和负分数统称分数C.正整数和负整数统称整数D.零既可以是正整数也可以是负整数4、一个直二面角内的一点到两个面的距离分别是3cm和4 cm ,求这个点到棱的距离为()[单选题] *A、25cmB、26cmC、5cm(正确答案)D、12cm5、300°用弧度制表示为()[单选题] *5π/3(正确答案)π/62π/32π/56、28.已知点A(2,3)、B(1,5),直线AB的斜率是()[单选题] *A.2B.-2C.1/2D.-1/2(正确答案)7、29.若(2,a)和(3,b)是直线y=x+k上的两点,那么这两点间的距离为()[单选题] *A.8B.10C.√2(正确答案)D.28、4.一个数是25,另一个数比25的相反数大- 7,则这两个数的和为[单选题] *A.7B. - 7(正确答案)C.57D. - 579、已知二次函数f(x)=2x2-x+2,那么f(-2)的值为()。
[单选题] *12(正确答案)28310、21.已知集合A={x|-2m},B={x|m+1≤x≤2m-1}≠?,若A∩B=B,则实数m的取值范围为___. [单选题] *A 2≤x≤3(正确答案)B 2<x≤3C 2≤x<3D 2<x<311、9.点(-3,4)到y轴的距离是()[单选题] *A.3(正确答案)B.4C.-3D.-412、8.修建高速公路时,经常把弯曲的公路改成直道,从而缩短路程,其道理用数学知识解释正确的是()[单选题] *A.线段可以比较大小B.线段有两个端点C.两点之间,线段最短(正确答案)D.过两点有且只有一条直线13、-950°是()[单选题] *A. 第一象限角B. 第二象限角(正确答案)C. 第三象限角D. 第四象限角14、48.如图,M是AG的中点,B是AG上一点.分别以AB、BG为边,作正方形ABCD和正方形BGFE,连接MD和MF.设AB=a,BG=b,且a+b=10,ab=8,则图中阴影部分的面积为()[单选题] *A.46B.59(正确答案)C.64D.8115、12.如图,数轴上的两个点分别表示数a和﹣2,则a可以是()[单选题] *A.﹣3(正确答案)B.﹣1C.1D.216、7.已知点A(-2,y1),B(3,y2)在一次函数y=-x+b的图象上,则( ) [单选题]* A.y1 > y2(正确答案)B.y1 < y2C.y1 ≤y2D.y1 ≥y217、下列计算正确的是( ) [单选题] *A. 9a3·2a2=18a?(正确答案)B. 2x?·3x?=5x?C. 3 x3·4x3=12x3D. 3y3·5y3=15y?18、为筹备班级联欢会,班长对全班同学爱吃哪几种水果做了民意调查,然后决定买什么水果,最值得关注的应该是统计调查数据的( ) [单选题] *A.中位数B.平均数C.众数(正确答案)D.方差19、二次函数y=3x2-4x+5的常数项是()。
A-level基础数学2009年1月C2试题答案

GCEJanuary 20096664 Core Mathematics C2 Mark SchemeQuestion NumberScheme Marks6(a) b a +++=24016)2(f or f (1)15a b −=−−+M1 A1Finds 2nd remainder and equates to 1st 1640215a b a b ⇒+++=−−+ M1 A120−=aA1cso (5) (b) 03)3(5)3()3(f 34=+−−+−=−b aM1 A1ft81 – 135 + 60 + b = 0 gives b = -6A1 cso (3) [8]Alternative for (a)(a) Uses long division, to get remainders as b + 2a + 56 or b – a - 4 or correct equivalentM1 A1 Uses second long division as far as remainder term, to get b + 2a + 56 = b – a - 4 or correct equivalent M1 A120−=aA1cso (5) Alternative for (b)(b) Uses long division of 43520x x x b +−+ by (x + 3) to obtain 322618x x x a +−++( with their value for a )M1 A1ftGiving remainder b + 6 = 0 and so b = -6A1 cso(3) [8] Notes (a) M1 : Attempts f(2±) or f(1±)A1 is for the answer shown (or simplified with terms collected ) for one remainderM1: Attempts other remainder and puts one equal to the other A1: for correct equation in a (and b ) then A1 for 20−=a cso (b) M1 : Puts f (3)0±=A1 is for f( -3) = 0, (where f is original function), with no sign or substitution errors (follow through on ‘a ’ and could still be in terms of a ) A1: b = -6 is cso.Alternatives (a) M1: Uses long division of 435x x ax b +++ by (x 2±) or by (x 1±) as far as threeterm quotientA1: Obtains at least one correct remainderM1: Obtains second remainder and puts two remainders (no x terms) equal A1: correct equation A1: correct answer a = -20 following correct work. (b) M1: complete long division as far as constant (ignore remainder)A1ft: needs correct answer for their a A1: correct answerBeware: It is possible to get correct answers with wrong working . If remainders are equated to 0 in part (a) both correct answers are obtained fortuitously. This could score M1A1M0A0A0M1A1A0。
alevel2024春季考试试题

alevel2024春季考试试题Alevel 2024春季考试试题随着2024春季的到来,学生们正忙于备考Alevel考试。
Alevel考试是英国高中生的重要考试,对于学生们进入大学或职业生涯具有重要的影响。
为了帮助同学们更好地准备考试,我们整理了一套2024春季考试试题,希望能对大家有所帮助。
1. 英语(English)1.1 阅读理解(Reading Comprehension)阅读下面一篇短文,然后回答问题。
文章:...问题:...解答:...1.2 写作(Writing)请根据以下提示,写一篇关于环境保护的短文。
提示:...内容:...结论:...2. 数学(Mathematics)2.1 代数(Algebra)解以下方程组。
解答:...2.2 几何(Geometry)计算以下几何问题。
问题:...解答:...3. 物理(Physics)3.1 力学(Mechanics)问题:...解答:...3.2 电学(Electronics)问题:...解答:...4. 化学(Chemistry)4.1 有机化学(Organic Chemistry)问题:...解答:...4.2 物质与变化(Matter and Change)问题:...5. 生物(Biology)5.1 分子生物学(Molecular Biology)问题:...解答:...5.2 生态学(Ecology)问题:...解答:...以上是2024春季考试的试题,希望能为同学们的备考提供一定的帮助。
在备考过程中,同学们应该注重理论的学习和实践的练习,努力提高自己的知识水平和应试能力。
在英语考试中,阅读理解是一个重要的部分。
同学们需要通过大量的阅读来提高自己的理解能力,同时掌握一些阅读技巧,如寻找关键词,理解上下文等。
在写作方面,同学们应该注重语法和词汇的准确性,同时注意文章的结构和逻辑性。
在数学考试中,代数和几何是重点。
同学们需要熟练掌握代数的基本运算和方程的解法,同时理解几何的基本概念和定理。
2014年A-Level进阶数学纯数学试卷部分试题赏析

学习,凭借考试成绩申请大学.在英国,大多数的中学开设相当
广泛的A—Level课程,多达100多门,真正满足了学生的个性 化发展.在国内的各剑桥高中,考虑到中国学生的学习特点,更 由于师资的限制,各中心实际开设的课程要少很多,通常为英 语、数学、进阶数学、物理、化学、计算机、生物、会计、商业学、经 济学等课程. 2.A—Level进阶数学课程
年的考试大纲为例介绍A—Level进阶数学的数学教学. 1.评价方法 进阶数学需要参加两次考试,分别为纯数学和应用数学, 其中应用数学又包含统计和机械学,每门考试均为3小时,每 张试卷10一11个题目,全部为解答题,总分为100分,考试结束 后,剑桥考试中心根据全球考生的分数划分A、口、C、D、E、u六 个等级,E是通过,u为不通过,下表就是2014年5月/6月进阶 数学考试对每一个部分的评分等级.
224700
崔
辉
①当曰=∥时,△;4(口+1)2—4(口2—1)<O,解得o<一1.
②当曰={o}时,由两个根为。及韦达定={4}时,由两个根为4及韦达定理得
{;翟:二11)6≯解得口不存在.
④当B={0,4}时,由韦达定理得
nⅣ=一
错解的同学认为肘与Ⅳ无公共元素.
Zsln—_
:壶姚。s如川蛐扣=善cos÷㈦啪
zsm—二一 s¨l—写
例2
曲线C的参数方程为z=e‘一4t+3,),=8er,0≤
(1)求曲线C的长度(结果以e的形式表示).(2)曲线c 围绕并轴旋转一圈,求所得图形的表面积(结果以e和可的形式 表示). 赏析 本题主要考查曲线的参数方程,曲线长度公式,旋 转曲面的表面积公式以及定积分的相关知识.
F、l _、Ir }∥匕㈠F =、l_、l 0丁
trigonometry alevel试题
trigonometry alevel试题
以下是一份完整的A-Level三角学试题:
一、选择题
1.在直角三角形中,已知角A的正弦值为0.6,角B的正切值为-1,则角A的度数为:
A. 30度
B. 45度
C. 60度
D. 75度
2.若一个三角形的内角和为180度,则该三角形为:
A. 锐角三角形
B. 直角三角形
C. 钝角三角形
D. 等腰三角形
3.在等腰三角形ABC中,角B是角A的两倍,且角C等于60度,则角A的度数为:
A. 30度
B. 40度
C. 60度
D. 120度
二、填空题
1.在三角形ABC中,已知角A的正弦值、余弦值和正切值分别为sinA、cosA、tanA,则tanA = _______。
2.若一个三角形的三边长度分别为3、4和5,则该三角形的最大角为_______ 度。
3.在等腰直角三角形中,斜边长为2,则腰长为_______。
答案及解析见下表:。
英国高考数学试卷中文版
试卷名称:A-Level数学试卷考试时长:2小时30分钟总分:100分一、选择题(共20题,每题2分,共40分)1. 下列哪个数是平方根?A. √4B. √-4C. √0D. √92. 如果一个等差数列的第一项是2,公差是3,那么第五项是多少?A. 7B. 8C. 9D. 103. 已知函数f(x) = 2x - 3,求f(5)的值。
A. 7B. 8C. 9D. 104. 一个三角形的三个内角分别是30°、60°和90°,那么这个三角形是?A. 等腰三角形B. 等边三角形C. 直角三角形D. 钝角三角形5. 已知一个正方形的对角线长为10cm,求这个正方形的面积。
A. 50cm²B. 100cm²C. 50πcm²D. 100πcm²6. 如果一个数的平方是16,那么这个数是?A. 4B. -4C. 4 或 -4D. 07. 下列哪个不等式是正确的?A. 2x + 3 > 5B. 2x + 3 < 5C. 2x + 3 = 5D. 2x + 3 ≠ 58. 一个圆的半径增加了50%,那么这个圆的面积增加了多少?A. 25%B. 50%C. 100%D. 200%9. 如果一个二次方程的解是x = 2和x = 3,那么这个方程是?A. x² - 5x + 6 = 0B. x² - 6x + 8 = 0C. x² - 5x - 6 = 0D. x² - 6x - 8 = 010. 下列哪个数是立方根?A. ∛27B. ∛-27C. ∛0D. ∛811. 如果一个数的立方是64,那么这个数是?A. 4B. -4C. 4 或 -4D. 012. 下列哪个函数是反比例函数?A. y = x + 2B. y = 2xC. y = 2/xD. y = x²13. 一个长方体的长、宽、高分别是4cm、3cm和2cm,求这个长方体的体积。
2014年Alevel 数学试卷解析(精排版)
EDEXCEL GCE MATHEMATICSGeneral Instructions for Marking1.The total number of marks for the paper is 75.2.The Edexcel Mathematics mark schemes use the following types of marks:•M marks: method marks are awarded for ‘knowing a method and attempting to apply it’, unless otherwise indicated.•A marks: Accuracy marks can only be awarded if the relevant method (M) marks have been earned.•B marks are unconditional accuracy marks (independent of M marks)•Marks should not be subdivided.3.AbbreviationsThese are some of the traditional marking abbreviations that will appear in the mark schemes.•bod – benefit of doubt•ft – follow through•the symbol will be used for correct ft•cao – correct answer only•cso - correct solution only. There must be no errors in this part of the question to obtain this mark•isw – ignore subsequent working•awrt – answers which round to•SC: special case•oe – or equivalent (and appropriate)•dep – dependent•indep – independent•dp decimal places•sf significant figures•¿The answer is printed on the paper•The second mark is dependent on gaining the first mark4.All A marks are ‘correct answer only’ (cao.), unless shown, for example, as A1 ft toindicate that previous wrong working is to be followed through. After a misread however, the subsequent A marks affected are treated as A ft, but manifestly absurd answersshould never be awarded A marks.5.For misreading which does not alter the character of a question or materially simplify it,deduct two from any A or B marks gained, in that part of the question affected.6.If a candidate makes more than one attempt at any question:•If all but one attempt is crossed out, mark the attempt which is NOT crossed out.•If either all attempts are crossed out or none are crossed out, mark all the attempts and score the highest single attempt.7.Ignore wrong working or incorrect statements following a correct answer.General Principles for Core Mathematics Marking(But note that specific mark schemes may sometimes override these general principles). Method mark for solving 3 term quadratic: 1.Factorisationc pq q x p x c bx x =++=++where ),)(()(2, leading to x = …a mn c pq q nx p mx c bx ax ==++=++and where ),)(()(2, leading to x = …2.FormulaAttempt to use the correct formula (with values for a , b and c ).pleting the squareSolving02=++c bx x :0,022≠=±±⎟⎠⎞⎜⎝⎛±q c q b x , leading to x = …Method marks for differentiation and integration: 1.DifferentiationPower of at least one term decreased by 1. (1−→n nx x )2.IntegrationPower of at least one term increased by 1. (1+→n nxx )Use of a formulaWhere a method involves using a formula that has been learnt, the advice given in recent examiners’ reports is that the formula should be quoted first. Normal marking procedure is as follows:Method mark for quoting a correct formula and attempting to use it, even if there are mistakes in the substitution of values.Where the formula is not quoted, the method mark can be gained by implication from correct working with values, but may be lost if there is any mistake in the working.Exact answersExaminers’ reports have emphasised that where, for example, an exact answer is asked for, or working with surds is clearly required, marks will normally be lost if the candidate resorts to using rounded decimals.Answers without workingThe rubric says that these may not gain full credit. Individual mark schemes will give details of what happens in particular cases. General policy is that if it could be done “in your head”, detailed working would not be required.Notes(a) M1: Attempt to differentiate – power reduced 1n n→or 3x becomes 3x x−A1: two correct terms ( of the three shown). They may be unsimplifiedA1: fully correct and simplified then isw (any equivalent simplified form acceptable) (b) M1: Attempt to integrate original f(x)– one power increased 1n nx x+→A1: Two of the four terms in x correct unsimplified – (ignore lack of constant here) A1: Three terms correct unsimplified – (ignore lack of constant here)A1: All correct simplified with constant – allow -1x for –xN.B Integrating answer to part (a) is M0Notes(a)(b) (c)M1: Attempt to use formula correctly (implied by first term correct, or given as 0.67, or third term following through from their second etc) A1: two correct answersA1: 3 correct answers (allow 0.6 recurring but not 0.667) Look for the values. Ignore the label r u B1: cao (NB Use of AP is B0)M1:Uses sum of at least 3 terms found from part (a)) (may be implied by correct answer). Attempt to sum an AP here is M0.A1: obtains 33(sum of three adjacent terms)×or 11(sum of nine adjacent terms)× A1: - 11 cao ( -11 implies both A marks) N.B. Use of n = 99 is M1A0A0(b)to give printed answer including = 0M1: Solving the correct quadratic equation (allow sign errors), by the usual methods (see notes) – implied by correct answersA1: Both answers needed – allow 0.25 and awrt – 0.33M1 Uses inverse cosine to obtain two correct values for x for their values of cos x e.g. (75.5 and 109.4 or 109.5) or (75.5 and 284.5) or (109.5 and 250.5) – allow truncated answers or awrt here.A1: All four correct – allow awrt. Ignore extra answers outside range but lose last A mark for extra answers inside rangeAnswers in radians are 1.3, 5.0, 1.9 and 4.4 Allow M1A0 for two or more correct asnwersQuestion Number SchemeMarks 8.kx 2x ++82k +()7=Uses 2−4b ac with a k ,b ==8 and attempt at c =2(k + 7)M1 b a −=c 464−56k −228k or 6456k =+8k 2o .e . A1 Attempts to solve 2"7k k +−8=0"to give k =dM1 ⇒Critical values, k 1,=−8.A1cso M1 Uses 4b a −<c 0or 22b 4<ac or ac 4 −b 2>02k k +−78>0 gives 1(or)k k ><8−M1 A1 [7]7 marksNotesM1: Attempts 24b ac − for ,8a k b == and c = 2(k +7) or attempt at c from quadratic = 0 (may omit bracket or make sign slip or lose the 2, so 2k +7 or k + 7 for example)oruses quadratic formula to solve equation or uses on two sides of an equation or inequation A1: Correct three term quadratic expression for 24b ac − - (may be under root sign)dM1: Uses factorisation, formula, or completion of square method to find two values for k , or finds two correct answers with no obvious method for their three term quadratic A1: Obtains 1 and -8M1: states 22404b ac or b ac −<< anywhere (may be implied by the following work)M1: Chooses outside region ( k < Their Lower Limit Their Upper Limit k >) for appropriate 3 term quadratic inequality . Do not award simply for diagram or table.A1: 1or 8k k ><− - allow anything which clearly indicates these regions e.g. (,8)−∞− or (1,)∞ 1,8k k ><− is A1 but k > 1 and k < -8 is A0but x > 1, x < -8 is A0 ( only lose 1 mark for using x instead of k ) and 1(or)8k k ≥≤−is A0 Also 1< k < -8 is M1 A0N.B. Lack of working: If there is no mention of 2240or 4b ac b ac −<< then just the correct answer 1,8k k ><− can imply the last M1M1A1 1,8k k ≥≤− can imply M0M1A01,8k k ><− can imply M1M1A0 Anything else needs to apply schemeMethod markfor harmoniccurve i.e. anysine or cosinecurveAccuracy forcorrect sectionand positionrelative to the (0 , ½ ) ;Notes for Question 14(a) M1: Puts equations equaldM1 Solves quadratic to obtain x =A1: both answers correctdM1: finds y =A1: both correctB1: Correct integration of one of the quadratic expression (given in the mark scheme) to give one of the givencubic expression (ignore limits). Allow correct answer even if terms not collected nor simplified. Sign errors (b)subtracting in alternative methods before integration gain B0B1: Line intersection correct (see 1.5)B1: curve intersection correct (see 5)M1: Uses correct combination of correct areas (allow numerical slips) so(i)Area of triangle using their “6” – their “1.5” times their “9” MINUS area beneath curve between their 5 and their 6(ii) Area of triangle using their “5” – their “1.5” times their “7” PLUS area between curves between their 5 and their 6(iii) Subtracts area below axis from area between curvesTHEIR 1.5 must NOT BE ZERO!M1: Attempts second area (so area of a triangle relevant to the method- or integral of the linear functionwith relevant limits- or integral of original quadratic in second alternative method)M1: Uses their limits (even zero) correctly on any cubic expression (subtracting either way round) Can begiven for wrong limits or for wrong areas. No evidence of substitution of limits is M0A1: Final answer – not decimal – csoAlternative methods to part (d)(i)Use equation x y 22++ax +by +c =0and substitute three points, usually (0,3), (6,11) and another point on the circle maybe (-2,17) or (-8,9) - not point Z Solves simultaneous equations a = 2, b = -20 and c = 51(ii) Uses centre to write a = and b = (doubles x coordinate and y coordinate respectively, "2"and ±±"20")Obtains a = 2 and b = -20 (or just writes these values down so these answers imply M1A1) Completes method to find c , (could substitute one of the points on the circle) or could find r Accurate work e.g. r 2=50 or e.g. +x y 222+−x 20y =(−8)2+2+928×−−20×9 = c = 51M1 dM1A1,A1,A1 M1 A1 dM1 A1 A1。
alevel试题及答案
alevel试题及答案1. 请解释牛顿第三定律。
答案:牛顿第三定律,也称为作用与反作用定律,指出对于任何两个相互作用的物体,它们之间的力是相等且相反的。
这意味着当一个物体对另一个物体施加一个力时,另一个物体也会对第一个物体施加一个大小相等但方向相反的力。
2. 描述光的波粒二象性。
答案:光的波粒二象性是指光既表现出波动性质,也表现出粒子性质。
作为波动,光具有波长和频率,能够产生干涉和衍射现象。
作为粒子,光由光子组成,光子具有能量和动量,可以被物体吸收或发射。
3. 解释什么是相对论。
答案:相对论是阿尔伯特·爱因斯坦提出的物理理论,它包括狭义相对论和广义相对论两部分。
狭义相对论主要处理在没有引力作用下的高速运动物体,指出时间和空间是相对的,并且光速在任何惯性参考系中都是恒定的。
广义相对论则是关于引力的理论,它将引力解释为物体在时空曲率中的运动。
4. 列举并解释两种常见的遗传变异类型。
答案:遗传变异是指基因序列的变化,常见的变异类型包括:- 点突变:指DNA序列中单个核苷酸的替换、插入或缺失,可能导致氨基酸序列的改变。
- 染色体重排:涉及染色体片段的移动、缺失或重复,可能导致基因表达的改变或疾病。
5. 描述细胞周期的四个阶段。
答案:细胞周期是细胞生长、复制并分裂为两个新细胞的连续过程,包括以下四个阶段:- G1期:细胞生长和准备DNA复制。
- S期:DNA复制。
- G2期:细胞继续生长,准备进行有丝分裂。
- M期:有丝分裂发生,细胞分裂为两个新的细胞。
6. 解释什么是热力学第一定律。
答案:热力学第一定律,也称为能量守恒定律,指出在一个封闭系统中,能量不能被创造或消灭,只能从一种形式转换为另一种形式。
在热力学过程中,系统吸收的热量等于系统内能的增加和对外做的功之和。
7. 列举并解释两种常见的生态系统服务。
答案:生态系统服务是指生态系统为人类社会提供的直接或间接利益,包括:- 生物多样性保护:生态系统通过维持物种多样性,有助于保持生态平衡和生态系统的稳定性。
- 1、下载文档前请自行甄别文档内容的完整性,平台不提供额外的编辑、内容补充、找答案等附加服务。
- 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
- 3、如文档侵犯您的权益,请联系客服反馈,我们会尽快为您处理(人工客服工作时间:9:00-18:30)。
alevel数学试卷答案
一、填空题
1.一元二次方程的一般形式是__________.
2将方程-5x2+1=6x化为一般形式为__________.
3.将方程(x+1)2=2x化成一般形式为__________.
4.方程2x2=-8化成一般形式后,一次项系数为__________,常数项为
__________.
5.方程5(x2-x+1)=-3x+2的一般形式是__________,其二次项是
__________,一次项是__________,常数项是__________.
6.若ab≠0,则x2+x=0的常数项是__________.
7.如果方程ax2+5=(x+2)(x-1)是关于x的一元二次方程,则a__________.
8.关于x的方程(m-4)x2+(m+4)x+2m+3=0,当m__________时,是一元二次方程,当m__________时,是一元一次方程.
二、选择题
1.下列方程中,不是一元二次方程的是( )
A.2x2+7=0
B.2x2+2x+1=0
C.5x2++4=0
D.3x2+(1+x) +1=0
2.方程x2-2(3x-2)+(x+1)=0的一般形式是( )
A.x2-5x+5=0
B.x2+5x+5=0
C.x2+5x-5=0
D.x2+5=0
3.一元二次方程7x2-2x=0的二次项、一次项、常数项依次是( )
A.7x2,2x,0
B.7x2,-2x,无常数项
C.7x2,0,2x
D.7x2,-2x,0
4.方程x2-=(-)x化为一般形式,它的各项系数之和可能是( )
A. B.-C. D.
5.关于x的方程(ax+b)(d-cx)=m(ac≠0)的二次项系数是ac,则常数项为( )
A.m
B.-bd
C.bd-m
D.-(bd-m)
6.若关于x的方程a(x-1)2=2x2-2是一元二次方程,则a的值是( )
A.2
B.-2
C.0
D.不等于2
7.若x=1是方程ax2+bx+c=0的解,则( )
A.a+b+c=1
B.a-b+c=0
C.a+b+c=0
D.a-b-c=0
8.关于x2=-2的说法,正确的是( )
A.由于x2≥0,故x2不可能等于-2,因此这不是一个方程
B.x2=-2是一个方程,但它没有一次项,因此不是一元二次方程
C.x2=-2是一个一元二次方程
D.x2=-2是一个一元二次方程,但不能解参考答案
一、1.ax2+bx+c=0(a≠0)
2.5x2+6x-1=0
3.x2+1=0
4.0 8
5.5x2-2x+3=0 5x2 -2x 3
6.0
7.≠1
8.≠4 =4
二、1.C 2.A 3.D 4.D 5.D 6.A 7.C 8.C。