{"question": "一种花瓣的花粉颗粒直径用科学记数法表示为 $6.5\\times 10^{-6}$,这个数用小数表示为____", "options": ["0.00065", "0.000065", "0.0000065", "0.00000065"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "某工艺品车间有 20名工人,平均每人每天可制作 12个大花瓶或 10个小饰品,已知2 个大花瓶与 5个小饰品配成一套,则要安排 x名工人制作大花瓶,才能使每天制作的大花瓶和小饰品刚好配套,方程正确的是____", "options": ["$2\\times12\\left(x-20\\right)=5\\times10x$", "$2\\times12x=5\\times10\\left(20-x\\right)$", "$5\\times12\\left(x-20\\right)=2\\times10x$", "$5\\times12x=2\\times10\\left(20-x\\right)$"], "answer": "D", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in One Variable"} {"question": "点A(a,4) 、点B(3,b) 关于 轴对称,则$(a+b)^{2010}$ 的值为____", "options": ["0", "-1", "1", "$7^{2010}$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "为调查某校九年级学生体育锻炼情况,下列调查对象最合适的____", "options": ["选50名男生", ".选一个班级的学生", "选50名女生", "随机选取九年级50名学生"], "answer": "D", "topic": "Middle--Basic Probability and Statistics--Data Collection and Organization"} {"question": "把方程$\\frac{x+1}{0.4}-\\frac{0.2x-1}{0.7}=1$中分母化整数,其结果应为____", "options": ["$\\frac{10x+1}{4}-\\frac{2x-1}{7}=1$", "$\\frac{10x+1}{4}-\\frac{2x-1}{7}=10$", "$\\frac{10x+10}{4}-\\frac{2x-10}{7}=1$", "$\\frac{10x+10}{4}-\\frac{2x-10}{7}=10$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Fractions"} {"question": "因式分解$x^{2}+m x-12=\\left(x+p\\right)\\left(x+q\\right)$,其中 m,p ,q 都为整数,则这样的m的最大值是____", "options": ["1", "4", "11", "12"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "若单项式$x^my^2$ 与$-2x^3y^n$ 的和仍是单项式,则$n^m$的值为____", "options": ["-8", "-9", "9", "8"], "answer": "D", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "下列说法不正确的是____", "options": ["用一个平面去截正方体,截面可能是七边形", "用一个平面去截一个球,截面一定是圆", "棱柱的截面不可能是圆", "用一个平面去截圆锥,截面可能是圆"], "answer": "A", "topic": "Middle--Basic Geometry--Basic Concepts of Geometry"} {"question": "下列从左到右的变形,错误的是____", "options": ["$-m+n=-\\left(m+n\\right)$", "$-a-b=-(a+b )$", "$\\left(m-n\\right)^{3}=-\\left(n-m\\right)^{3}$", "$(y-x)^{2}=\\left(x-y\\right)^{2}$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "下列式子计算正确的是____", "options": ["$2x+3y=5x y$", "$3a^{2}b-5b a^{2}=-2a^{2}b$", "$-\\left(3x-1\\right)=-3x-1$", "$\\left(a-b\\right)-\\left(c-b\\right)=a-2b-c$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "下列四个判断中,不正确的是____", "options": ["0既不是正数也不是负数", "0的倒数是0", "0的相反数是 0", "零是绝对值最小的有理数"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "下列方程中是一元一次方程的是____", "options": ["$1-\\frac{x}{2}=3y-2$", "$\\frac{1}{y}-2=y$", "$3x+1=2x$", "$3x^{2}+1=0$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in One Variable"} {"question": "$\\sqrt4$的平方根是____", "options": ["$2$", "$\\pm2$", "$\\sqrt 2$", "$\\pm \\sqrt 2$"], "answer": "D", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "若⊙P的半径为5,圆心P的坐标为(-3,4),则平面直角坐标系的原点O与⊙P的位置关系是____", "options": ["在⊙P内", "在⊙P上", "在⊙P外", "无法确定"], "answer": "B", "topic": "Middle--Basic Geometry--Basic Concepts of Circles"} {"question": "下列语句中是命题的有____①如果两个角都等于70°,那么这两个角是对顶角; ②三角形内角和等于180°; ③画线段AB=3 cm.", "options": ["0个", "1个", "2个", "3个"], "answer": "C", "topic": "Middle--Basic Geometry--Basic Concepts of Geometry"} {"question": "某种产品,商品的标价为120元,若以九折降价出售,相对于进货价仍获利 20%,该商品的进货价为____", "options": ["80元", "85元", "90元", "95元"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in One Variable"} {"question": "下列各式中正确的是____", "options": ["$\\sqrt{(-7)^{2}}=-7$", "$\\sqrt{9}=\\pm3$", "$(-\\sqrt{2})^{2}=4$", "$\\sqrt{48}-\\sqrt{3}=3\\sqrt{3}$"], "answer": "D", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "某工厂一月份生产机器100台,计划二、三月份共生产机器240台,设二、三月份的平均增长率为x,则根据题意列出方程是____", "options": ["$100(1+x)^2=240$", "$100(1+x)+100(1+x)^2=240$", "$100+100(1+x)+100(1+x)^2=240$", "$100(1-x)^2=240$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in One Variable"} {"question": "关于x的一元二次方程$x^2-3x+m=0$有两个不相等的实数根,则实数m的值范围为____", "options": ["$m\\geq \\frac{9}{4}$", "$m< \\frac{9}{4}$", "$m=\\frac{9}{4}$", "$m< -\\frac{9}{4}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Quadratic Equations in One Variable"} {"question": "已知单项式 $2x^{3}y^{1+2m}$与 $3x^{n+1}y^{3}$的和是单项式,则 $m+n$的值是____", "options": ["-3", "3", "6", "-6"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "下列各式运算的结果为$a^6$的是____", "options": ["$a^{3}\\cdot a^{3}$", "$(a^3)^3$", "$a^3+a^3$", "$a^{12} \\div a^2$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "某校组织七年级学生外出研学, (1)班人数38人,居各班之首,(2) 班人数 30人,位居第二,且这两个班男生一共有30人参加,则下列说法一定正确的是:____", "options": ["(1)班女生比 (2)班男生人数多", "(2)班女生比 (1)班男生人数多", "(2)班女生比 (2)班男生人数多", "(1)班女生比 (1)班男生人数多"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Basic Concepts of Inequalities"} {"question": "一元二次方程$4x^2+1=4x$的根的情况是____", "options": ["没有实数根", "只有一个实数根", "有两个相等的实数根", "有两个不相等的实数根"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Quadratic Equations in One Variable"} {"question": "下列代数式中不是单项式的是____", "options": ["$-12a b$", "$\\frac{2}{\\pi}$", "$\\frac{2x-3y}{5}$", "$0$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "使二次根式$\\sqrt{x-2}$ 有意义的x的取值范围为____", "options": ["$x>2$", "$x\\geq 2$", "$x=2$", "$x\\neq2$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Basic Concepts of Inequalities"} {"question": "分式$\\frac{xy}{x+y}$中 x,y 的值都扩大到原来的 倍,则分式的值____", "options": ["扩大到原来的9倍", "不变", "缩小到原来的$\\frac{1}{3}$", "扩大到原来的3倍"], "answer": "D", "topic": "Middle--Basic Numbers and Algebra--Fractions"} {"question": "下列式子从左到右变形不正确的是____", "options": ["$\\frac{ax}{ay}=\\frac{x}{y}$", "$\\frac{y}{x}=\\frac{ay}{ax}$", "$\\frac{(a^{2}+1) x}{(a^{2}+1)y}=\\frac{x}{y}$", "$\\frac{y}{x}=\\frac{(a^{2}+1)y}{\\left(a^{2}+1\\right)x}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Fractions"} {"question": "如果 $y=-x+3$,且 $x\\neq y$,那么代数式$\\frac{x^{2}}{x-y}+\\frac{y^{2}}{y-x}$的值为____", "options": ["$3$", "$-3$", "$\\frac{1}{3}$", "$-frac{1}{3}$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "在实数 $\\sqrt{5}$,$\\frac{7}{22}$, $\\sqrt[3]{-8}$, $0$, $-1.414$, $\\frac{\\pi}{2}$, $\\sqrt 36$, $0.1010010001$中,无理数有____", "options": ["2个", "3个", "4个", "5个"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "下列各式$\\frac{a-b}{2}$,$\\frac{x+3}{x}$ ,$\\frac{5+y}{\\pi}$ ,$\\frac{x^2}{4}$ ,$\\frac{a+b}{a-b}$ ,$\\frac{x-y}{m}$ , 中分式有____个", "options": ["2", "3", "4", "5"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Fractions"} {"question": "如果$\\sqrt {(2a-1)^2}=1-2a$,则____", "options": ["$a< \\frac{1}{2}$", "$a \\leq\\frac{1}{2}$", "$a> \\frac{1}{2}$", "$a \\geq \\frac{1}{2}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Basic Concepts of Inequalities"} {"question": "一艘轮船在静水中的最大航速是 30km/h,它以最大航速沿江顺流航行90km所用时间,与它以最大航速逆流航行60km所用时间相等.如果设江水的流速为x km/h,所列方程正确的是____", "options": ["$\\frac{90}{x+30}=\\frac{60}{x-30}$", "$\\frac{60}{x+30}=\\frac{90}{x-30}$", "$\\frac{90}{x+30}=\\frac{60}{30-x}$", "$\\frac{60}{x+30}=\\frac{90}{30-x}$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in One Variable"} {"question": "将二次函数$y=x^2-4x+1$ 化成 $y=a(x-h)^2+k$的形式为____", "options": ["$y=\\left(x-4\\right)^2+1$", "$y=(x-4)^2-3$", "$y=(x-2)^2-3$", "$y=(x+2)^2-3$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Quadratic Functions"} {"question": "$|-2020|$的倒数是____", "options": ["$2020$", "$\\frac{1}{2020}$", "$-\\frac{1}{2020}$", "$-2020$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "下列计算结果正确的是____", "options": ["$\\sqrt{2}+\\sqrt{5}=\\sqrt{7}$", "$2\\sqrt{2}\\times2\\sqrt{3}=2\\sqrt{6}$", "$3\\sqrt{2}-\\sqrt{2}=3$", "$\\sqrt{27}\\div\\sqrt{3}=3$"], "answer": "D", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "为了简明扼要地说明空气中多种混合气体情况,使用的统计图最好是____", "options": ["条形统计图", "折线统计图", "扇形统计图", "频数分布直方图"], "answer": "C", "topic": "Middle--Basic Probability and Statistics--Data Analysis"} {"question": "关于x的方程$x^2-2x+n=0$ 无实数根,则一次函数$y=(n-1)x-n$ 的图像不经过____", "options": ["第一象限", "第二象限", "第三象限", "第四象限"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Quadratic Equations in One Variable"} {"question": "小李2019年全年支付宝总支出金额为20400元,将20400用科学计数法可表示为____", "options": ["$0.204\\times10^5$", "$2.04\\times10^4$", "$20.4\\times10^3$", "$204\\times10^2$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "去年济川中学有近1千名考生参加中考,为了了解这些考生的数学成绩,从中抽取50名考生的数学成绩进行统计分析,以下说法正确的是____", "options": ["这50名考生是总体的一个样本", "近1千名考生是总体", "每位考生的数学成绩是个体", "50名学生是样本容量"], "answer": "C", "topic": "Middle--Basic Probability and Statistics--Data Collection and Organization"} {"question": "要调查某城区七年级8000名学生对禁毒知识的了解情况,下列调查方式最合适的是____", "options": ["在某校七年级学生中随机选取180名学生", "在城区七年级学生中随机选取180名女生", "在城区七年级学生中随机选取180名学生", "在某校七年级学生中随机选取180名男生"], "answer": "C", "topic": "Middle--Basic Probability and Statistics--Data Collection and Organization"} {"question": "在Rt△ABC中,∠C=90°,BC=3,AB=5,则sinA的值为____", "options": ["$\\frac{3}{5}$", "$\\frac{4}{5}$", "$\\frac{3}{4}$", "以上都不对"], "answer": "A", "topic": "Middle--Basic Geometry--Basics of Triangles"} {"question": "下列说法:①“掷一枚质地均匀的硬币,朝上一面可能是正面”;②“从一副普通扑克牌中任意抽取一张,点数一定是3”____", "options": ["只有①正确", "只有②正确", "①②都正确", "①②都错误"], "answer": "A", "topic": "Middle--Basic Probability and Statistics--Data Analysis"} {"question": "$2020$的相反数是____", "options": ["$-\\frac{1}{2000}$", "$\\frac{1}{2000}$", "$2020$", "$-2020$"], "answer": "D", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "﹣(﹣2019)的相反数是____", "options": ["$-2019$", "$2019$", "$\\frac{1}{2019}$", "$-\\frac{1}{2019}$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "下列运算结果正确的是____", "options": ["$2\\sqrt{2}+3\\sqrt{8}=5\\sqrt{10}$", "$\\sqrt{36}=\\pm6$", "$a^{2}\\div a^{6}=\\frac{1}{a^{4}}\\left(a\\neq0\\right)$", "$2^{-3}=-8$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "若代数式 $\\frac{x}{x-3}$的值为零,则实数x的值为____", "options": ["x =0", "x≠0", "x =3", "x≠3"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Fractions"} {"question": "要使分式$\\frac{x}{x-1}$有意义,则x的取值范围是____", "options": ["$x\\neq 1$", "$x\\neq 0$", "$01$", "$m=1$", "$m<1$", "$m<4$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Quadratic Functions"} {"question": "$-2$的绝对值是____", "options": ["$-2$", "$2$", "$\\frac{1}{2}$", "$-\\frac{1}{2}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "在下列运算中,正确的是____", "options": ["$(x-y)^2=x^2-y^2$", "$(a+2)(a-3)=a^2-6$", "$(a+2b)^2=a^2+4ab+4b^2$", "$(2x-y)(2x+y)=2x^2-y^2$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "已知∠A为锐角,且sinA=$\\frac{\\sqrt{3}}{2}$ ,那么∠A等于____", "options": ["15°", "30°", "45°", "60°"], "answer": "D", "topic": "Middle--Basic Geometry--Basics of Triangles"} {"question": "一元二次方程$x^2+6x-6=0$配方后化为____", "options": ["$(x-3)^2=3$", "$(x-3)^2=15$", "$(x+3)^2=15$", "$(x+3)^2=3$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Quadratic Equations in One Variable"} {"question": "平面直角坐标系中,直线 $y=-\\frac{1}{2}x+2$和x、y轴交于A、B两点,在第二象限内找一\t点P,使△PAO和△AOB相似的三角形个数为____", "options": ["2", "3", "4", "5"], "answer": "C", "topic": "Middle--Basic Geometry--Basic Concepts of Geometry"} {"question": "据统计, 2019年安徽省常住人口数为6323.6万人.请将6323.6万用科学记数法表示为____", "options": ["$6.3036\\times10^3$", "$6.3036\\times10^4$", "$6.3036\\times10^7$", "$6.3036\\times10^8$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "下列运算结果正确的是____", "options": ["$5x-x=5$", "$2x^{2}+2x^{3}=4x^{5}$", "$-4b+b=-3b$", "$a^{2}b-a b^{2}=0$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "方程$2x+1=3$的解是____", "options": ["$x=-1$", "$x=1$", "$x=2$", "$x=-2$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in One Variable"} {"question": "正方形是轴对称图形,对称轴有____条", "options": ["2", "3", "4", "5"], "answer": "C", "topic": "Middle--Basic Geometry--Quadrilaterals"} {"question": "下列二次根式中,是最简二次根式的是____", "options": ["$\\sqrt {17}$", "$\\sqrt {27}$", "$\\sqrt {\\frac{1}{2}}$", "$\\sqrt {a^2}$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "$-2$的倒数是____", "options": ["$-2$", "$2$", "$-\\frac{1}{2}$", "$\\frac{1}{2}$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "若三角形三边分别为 a,b ,c ,且分式$\\frac{ab-ac+bc-b^2}{a-c}$的值为0 ,则此三角形一定是____", "options": ["不等边三角形", "腰与底边不等的等腰三角形", "等边三角形", "直角三角形"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "反比例函数$y=\\frac{6}{x}$ 的图象位于____", "options": ["第一、第二象限", "第一、第三象限", "第二、第三象限", "第二、第四象限"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Inverse Proportion Functions"} {"question": "$x=2$是方程$mx+5=0$的解,则函数$y=mx-2$的图象不经过____", "options": ["第一象限", "第二象限", "第三象限", "第四象限"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in One Variable"} {"question": "一元二次方程$x^2-x=0$的根是____", "options": ["$x=1$", "$x=0$", "$x_1=0, x_2=1$", "$x_1=0, x_2=-1$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Quadratic Equations in One Variable"} {"question": "A,B,C 三点在同一直线上,线段$AB=5cm$ ,$BC=4cm$ ,那么A ,C 两点的距离是____", "options": ["1cm", "9cm", "1cm或9cm", "以上答案都不对"], "answer": "C", "topic": "Middle--Basic Geometry--Basic Concepts of Geometry"} {"question": "a表示一个一位数, b表示一个两位数,若把 a放在 b的左边,组成一个三位数,则这个三位数表示为____", "options": ["a+b", "10a+b", "100a+b", "10b+a"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "下面是某同学在一次测验中的计算摘录:①$3a+2b=5ab$ ;②$4m^3n-5mn^3=-m^3n$ ;③ $3x^{3}\\cdot\\left(-2x^{2}\\right)=-6x^{5}$;④ $4a^{3}b\\div\\left(-2a^{2}b\\right)=-2a$;⑤$(a^3)^2=a^5$ ;⑥$\\left(-a\\right)^{2}\\div \\left(-a\\right)=-a^{2}$ .其中正确的个数有____", "options": ["1个", "2个", "3个", "4个"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "某蔬菜公司收购到某种蔬菜140吨,准备加工上市销售.该公司的加工能力是:每天可以精加工6吨或粗加工16吨.现计划用15天完成加工任务,该公司应按排几天精加工,几天粗加工?设安排x天精加工,y 天粗加工.为解决这个问题,所列方程组正确的是____", "options": ["$\\left\\{\\begin{matrix}x+y=140\\\\ 16x+6y=15\\end{matrix}\\right.$", "$\\left\\{\\begin{array}{l}x+y=140\\\\ 6x+16y=15\\end{array}\\right.$", "$\\left\\{\\begin{matrix}x+y=15\\\\ 16x+6y=140\\end{matrix}\\right.$", "$\\left\\{\\begin{matrix}x+y=15\\\\ 6x+16y=140\\end{matrix}\\right.$"], "answer": "D", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in Two Variables"} {"question": "抛物线 $y=\\left(x-1\\right)^{2}+3$的顶点坐标为____", "options": ["(1,3)", "(-1,3)", "(-1,-3)", "(3,1)"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Quadratic Functions"} {"question": "下列正比例函数中, y的值随着x值的增大而减小的是____", "options": ["$y=0.2x$", "$y=\\left(\\sqrt{2}-\\sqrt{3}\\right)x$", "$y=\\frac{1}{5}x$", "$y=2x$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Inverse Proportion Functions"} {"question": "把一些图书分给某班的学习小组,如果每组分11本,则剩余1本;如果每组分12 本,则有一组少7本,设该班共有 x个学习小组,则 满足的方程是____", "options": ["$11x-1=12x-7$", "$11x+1=12x-7$", "$11x+1=12(x-1)-5$", "$11x-1=12(x-1)-5$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in One Variable"} {"question": "如$(x+m)$与$(x+3)$的乘积中不含x的一次项,则m的值为____", "options": ["-3", "3", "0", "1"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "下列运算中,正确的是____", "options": ["$2x+2y=2x y$", "$\\left(x y\\right)^{2}\\div\\frac{1}{x y}=(x y)^{3}$", "$\\left(x^2y^3\\right)^2=x^4y^5$", "$2x y-3y x=x y$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "工人师傅在给小明家安装晾衣架时,一般先在阳台天花板上选取两个点,然后再进行安装.这样做的数学原理是____", "options": ["过一点有且只有一条直线", "两点之间,线段最短", "两点确定一条直线", "连接两点之间的线段的长度叫两点间的距离"], "answer": "C", "topic": "Middle--Basic Geometry--Basic Concepts of Geometry"} {"question": "已知∠AOB,P是任一点,过点P画一条直线与OA平行,则这样的直线____", "options": ["有且仅有一条", "有两条", "不存在", "有一条或不存在"], "answer": "D", "topic": "Middle--Basic Geometry--Basic Concepts of Geometry"} {"question": "方程 $x^2=2x$的解是____", "options": ["$x_1=x_2=0$", "$x_1=x_2=2$", "$x_{1}=0,x_{2}=2$", "$x_{1}=0,x_{2}=\\sqrt{2}$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Quadratic Equations in One Variable"} {"question": "将抛物线$y=-2x^2+1$向左平移1个单位,再向下平移3个单位长度,所得的抛物线为____", "options": ["$y=-2(x-1)^2-2$", "$y=-2(x+1)^2-2$", "$y=-2(x-1)^2+4$", "$y=-2(x+1)^2+4$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Quadratic Functions"} {"question": "计算$0.25^{2013}\\times4^{2015}$____", "options": ["1", "8", "16", "2"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "4的平方根是____", "options": ["$2$", "$-2$", "$\\pm 2$", "$16$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "某边防哨卡运来一筐苹果,共有60个,计划每名战士分得数量相同的若干个苹果,结果还剩5个苹果;改为每名战士再多分1个,结果还差6个苹果.若设该哨卡共有x名战士,则所列方程为____", "options": ["$\\frac{60+6}{x}=\\frac{60-5}{x}-1$", "$\\frac{60+6}{x}=\\frac{60-5}{x}+1$", "$\\frac{60-6}{x}=\\frac{60+5}{x}-1$", "$\\frac{60-6}{x}=\\frac{60+5}{x}+1$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in One Variable"} {"question": "某超市为了吸引顾客,设计了一种返现促销活动:在一个不透明的箱子里放有4个相同的小球,球上分别标有“0元”、“10元”、“20元”、“30元”的字样。规定:顾客在本超市一次性消费满200元,就可以在箱子里一次性摸出两个小球,两球数字之和即为返现金额。某顾客刚好消费200元,则该顾客所获得返现金额不低于30元的概率是____", "options": ["$\\frac{3}{4}$", "$\\frac{2}{3}$", "$\\frac{1}{2}$", "$\\frac{1}{3}$"], "answer": "B", "topic": "Middle--Basic Probability and Statistics--Data Analysis"} {"question": "若 $\\sqrt {x-1}$在实数范围内有意义,则x的取值范围是____", "options": ["x≥1", "x>1", "x≤1", "x≠1"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "在平面直角坐标系中,点A(-4,-2)关于y轴对称的点的坐标是____", "options": ["(-4,2)", "(4,-2)", "(4,2)", "(-2,4)"], "answer": "B", "topic": "Middle--Basic Geometry--Basic Concepts of Geometry"} {"question": "若关于x的一元二次方程$x^2-4x+2m=0$有一个根为-1,则另一个根为____", "options": ["5", "-3", "-5", "4"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Quadratic Equations in One Variable"} {"question": "化简$\\frac{m^2-3m}{9-m^2}$的结果是____", "options": ["$\\frac{m}{m+3}$", "$-\\frac{m}{m+3}$", "$\\frac{m}{m-3}$", "$\\frac{m}{3-m}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "一直角三角形的两边长分别为3和4.则第三边的长为____", "options": ["5", "$\\sqrt 7$", "$\\sqrt 5$", "5或者$\\sqrt 7$"], "answer": "D", "topic": "Middle--Basic Geometry--Basics of Triangles"} {"question": "根据等式的性质,下列变形正确的是____", "options": ["如果 $2x=3$,那么 $\\frac{2x}{a}=\\frac{3}{a}$", "如果$x=y$ ,那么$x-5=5-y$", "如果 $x=y$,那么$-2x=-2y$", "如果 $\\frac{1}{2}x=6$,那么$x=3$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in One Variable"} {"question": "若 a,b 互为倒数,则 -4ab的值为____", "options": ["-4", "-1", "1", "0"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "点P(5,-4)关于 轴对称点是____", "options": ["(5,4)", "(5,-4)", "(4,-5)", "(-5,-4)"], "answer": "A", "topic": "Middle--Basic Geometry--Basic Concepts of Geometry"} {"question": "某种电脑病毒传播的非常快,如果一台电脑被感染,经过两轮感染后就会有81台电脑被感染,若病毒得不到有效控制,三轮感染后,被感染的电脑有____台.", "options": ["81", "648", "700", "729"], "answer": "D", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "不透明的袋子中装有红、绿小球各一个,除颜色外两个小球无其他差别.从中随机摸出一个小球,放回并摇匀,再从中随机摸出一个小球,那么第一次摸到红球、第二次摸到绿球的概率是( )", "options": ["$\\frac{1}{4}$", "$\\frac{1}{3}$", "$\\frac{1}{2}$", "$\\frac{3}{4}$"], "answer": "A", "topic": "Middle--Basic Probability and Statistics--Data Analysis"} {"question": "《义务教育课程标准$(2022$年版)》首次把学生学会炒菜纳入劳动教育课程,并做出明确规定.某班有$7$名学生已经学会炒的菜品的种数依次为:$3$,$5$,$4$,$6$,$3$,$3$,$4$.则这组数据的众数和中位数分别是( )", "options": ["$3$,$4$", "$4$,$3$", "$3$,$3$", "$4$,$4$"], "answer": "A", "topic": "Middle--Basic Probability and Statistics--Data Analysis"} {"question": "已知二次函数$y=x^{2}-2x-3$的自变量$x_{1}$,$x_{2}$,$x_{3}$对应的函数值分别为$y_{1}$,$y_{2}$,$y_{3}$.当$-1 \\lt x_{1} \\lt 0$,$1 \\lt x_{2} \\lt 2$,$x_{3} \\gt 3$时,$y_{1}$,$y_{2}$,$y_{3}$三者之间的大小关系是( )", "options": ["$y_{1} \\lt y_{2} \\lt y_{3}$", "$y_{2} \\lt y_{1} \\lt y_{3}$", "$y_{3} \\lt y_{1} \\lt y_{2}$", "$y_{2} \\lt y_{3} \\lt y_{1}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Quadratic Functions"} {"question": "若$\\triangle ABC$ ∽ $\\triangle DEF$,$BC=6$,$EF=4$,则$\\frac{{AC}}{{DF}}=\\left(\\ \\ \\right)$", "options": ["$\\frac{4}{9}$", "$\\frac{9}{4}$", "$\\frac{2}{3}$", "$\\frac{3}{2}$"], "answer": "D", "topic": "Middle--Basic Geometry--Basics of Triangles"} {"question": "下列计算中,正确的是( )", "options": ["$(a^{3})^{4}=a^{7}$", "$a^{2}\\cdot a^{6}=a^{8}$", "$a^{3}+a^{3}=a^{6}$", "$a^{8}\\div a^{4}=a^{2}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "反比例函数$y=\\frac{6}{x}$的图象分别位于( )", "options": ["第一、第三象限", "第一、第四象限", "第二、第三象限", "第二、第四象限"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Inverse Proportion Functions"} {"question": "小明同学对数据12,22,36.4■,52进行统计分析,发现其中一个两位数的个位数字被墨水污染已无法看清,则下列统计量与被污染数字无关的是( )", "options": ["平均数", "标准差", "方差", "中位数"], "answer": "D", "topic": "Middle--Basic Probability and Statistics--Data Analysis"} {"question": "小区新增了一家快递店,第一天揽件$200$件,第三天揽件$242$件,设该快递店揽件日平均增长率为$x$,根据题意,下面所列方程正确的是( )", "options": ["$200\\left(1+x\\right)^{2}=242$", "$200\\left(1-x\\right)^{2}=242$", "$200\\left(1+2x\\right)=242$", "$200\\left(1-2x\\right)=242$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in One Variable"} {"question": "下列图形中,对称轴条数最多的是( )", "options": ["等边三角形", "矩形", "正方形", "圆"], "answer": "D", "topic": "Middle--Basic Geometry--Basic Concepts of Geometry"} {"question": "$|-2|=\\left(\\ \\ \\right)$", "options": ["$-2$", "$2$", "$-\\frac{1}{2}$", "$\\frac{1}{2}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "小红在班上做节水意识调查,收集了班上$7$位同学家里上个月的用水量(单位:吨)如下:$5$,$5$,$6$,$7$,$8$,$9$,$10$.她发现,若去掉其中两个数据后,这组数据的中位数、众数保持不变,则去掉的两个数可能是( )", "options": ["$5$,$10$", "$5$,$9$", "$6$,$8$", "$7$,$8$"], "answer": "C", "topic": "Middle--Basic Probability and Statistics--Data Analysis"} {"question": "在一次视力检查中,某班$7$名学生右眼视力的检查结果为:$4.2$、$4.3$、$4.5$、$4.6$、$4.8$、$4.8$、$5.0$,这组数据的中位数和众数分别是( )", "options": ["$5.0$,$4.6$", "$4.6$,$5.0$", "$4.8$,$4.6$", "$4.6$,$4.8$"], "answer": "D", "topic": "Middle--Basic Probability and Statistics--Data Analysis"} {"question": "$2$的相反数是( )", "options": ["$2$", "$-2$", "$\\dfrac{1}{2}$", "$-\\dfrac{1}{2}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "估计$\\sqrt {29}$的值在( )", "options": ["$3$和$4$之间", "$ 4$和$5$之间", "$ 5$和$6$之间", "$ 6$和$7$之间"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "代数式$\\sqrt{x-3}$在实数范围内有意义,则$x$的取值范围是( )", "options": ["$x\\geqslant 3$", "$x \\gt 3$", "$x\\leqslant 3$", "$x \\lt 3$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Basic Concepts of Inequalities"} {"question": "化简$\\frac{1}{{a-3}}-\\frac{6}{{{a^2}-9}}$的结果是( )", "options": ["$\\frac{1}{{a+3}}$", "$a-3$", "$a+3$", "$\\frac{1}{{a-3}}$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "不等式组$\\left\\{{\\begin{array}{l}{x-1>0,}\\\\{x-3≤0}\\end{array}}\\right.$的解集是( )", "options": ["$x \\gt 1$", "$1 \\lt x \\lt 3$", "$1 \\lt x\\leqslant 3$", "$x\\leqslant 3$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Basic Concepts of Inequalities"} {"question": "$\\tan 45^{\\circ}$的值等于( )", "options": ["$2$", "$1$", "$\\frac{\\sqrt{2}}{2}$", "$\\frac{\\sqrt{3}}{3}$"], "answer": "B", "topic": "Middle--Basic Geometry--Basic Concepts of Geometry"} {"question": "方程$x^{2}+4x+3=0$的两个根为( )", "options": ["$x_{1}=1$,$x_{2}=3$", "$x_{1}=-1$,$x_{2}=3$", "$x_{1}=1$,$x_{2}=-3$", "$x_{1}=-1$,$x_{2}=-3$"], "answer": "D", "topic": "Middle--Basic Numbers and Algebra--Quadratic Equations in One Variable"} {"question": "某正方形广场的边长为 $4\\times 10^{2}m$,其面积用科学记数法表示为( )", "options": ["$4\\times 10^{4}m^{2}$", "$16\\times 10^{4}m^{2}$", "$1.6\\times 10^{5}m^{2}$", "$1.6\\times 10^{4}m^{2}$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "化简$(3a^{2})^{2}$的结果是( )", "options": ["$9a^{2}$", "$6a^{2}$", "$9a^{4}$", "$3a^{4}$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "计算$\\frac{{a+1}}{{a+2}}+\\frac{1}{{a+2}}$的结果是( )", "options": ["$1$", "$\\frac{2}{{a+2}}$", "$a+2$", "$\\frac{a}{{a+2}}$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Fractions"} {"question": "根据等式的性质,下列各式变形正确的是( )", "options": ["若$\\frac{a}{c}=\\frac{b}{c}$,则$a=b$", "若$ac=bc$,则$a=b$", "若$a^{2}=b^{2}$,则$a=b$", "若$-\\frac{1}{3}x=6$,则$x=-2$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in One Variable"} {"question": "不等式$3x-2 \\gt 4$的解集是( )", "options": ["$x \\gt -2$", "$x \\lt -2$", "$x \\gt 2$", "$x \\lt 2$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Basic Concepts of Inequalities"} {"question": "下列正确的是( )", "options": ["$\\sqrt{4+9}=2+3$", "$\\sqrt{4×9}=2\\times 3$", "$\\sqrt{{9^4}}=3^{2}$", "$\\sqrt{4.9}=0.7$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "赤道长约为$40000000m$,用科学记数法可以把数字$40000000$表示为( )", "options": ["$4\\times 10^{7}$", "$40\\times 10^{6}$", "$400\\times 10^{5}$", "$40000\\times 10^{3}$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "下列说法正确的是( )", "options": ["了解一批灯泡的使用寿命,应采用抽样调查的方式", "如果某彩票的中奖概率是 $1\\% $,那么一次购买 $100 $张这种彩票一定会中奖", "若甲、乙两组数据的平均数相同, $S_{甲}^{2}=2.5 $, $S_{乙}^{2}=8.7 $,则乙组数据较稳定", "“任意掷一枚质地均匀的骰子,掷出的点数是 $7 $”是必然事件"], "answer": "A", "topic": "Middle--Basic Probability and Statistics--Data Collection and Organization"} {"question": "不等式$x+2 \\gt 3$的解集是( )", "options": [".$x \\lt 1$", ".$x \\lt 5$", "$x \\gt 1$", ".$x \\gt 5$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Basic Concepts of Inequalities"} {"question": "已知圆锥的底面半径为5,高为12,则它的侧面展开图的面积是( )", "options": ["$60\\pi $", "$65\\pi $", "$90\\pi $", "$120\\pi $"], "answer": "B", "topic": "Middle--Basic Geometry--Basic Concepts of Geometry"} {"question": "若点$A(x_{1}$,$2)$,$B(x_{2}$,$-1)$,$C(x_{3}$,$4)$都在反比例函数$y=\\frac{8}{x}$的图象上,则$x_{1}$,$x_{2}$,$x_{3}$的大小关系是( )", "options": ["$x_{1} \\lt x_{2} \\lt x_{3}$", "$x_{2} \\lt x_{3} \\lt x_{1}$", "$x_{1} \\lt x_{3} \\lt x_{2}$", "$x_{2} \\lt x_{1} \\lt x_{3}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Inverse Proportion Functions"} {"question": "$-\\frac{3}{7}$的相反数是( )", "options": ["$\\frac{3}{7}$", "$-\\frac{3}{7}$", "$\\frac{7}{3}$", "$-\\frac{7}{3}$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "中国科学技术大学利用\"墨子号\"科学实验卫星,首次实现在地球上相距$1200$公里的两个地面站之间的量子态远程传输,对于人类构建全球化量子信息处理和量子通信网络迈出重要一步,$1200$这个数用科学记数法可表示为( )", "options": ["$0.12\\times 10^{4}$", "$1.2\\times 10^{4}$", "$1.2\\times 10^{3}$", "$12\\times 10^{2}$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "计算:$2x\\cdot (-3x^{2}y^{3})=\\left(\\ \\ \\right)$", "options": ["$6x^{3}y^{3}$", "$-6x^{2}y^{3}$", "$-6x^{3}y^{3}$", "$18x^{3}y^{3}$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "若反比例函数$y=\\frac{k}{x}(k\\neq 0)$的图象经过点$\\left(2,-3\\right)$,则它的图象也一定经过的点是( )", "options": ["$(-2,-3)$", "$(-3,-2)$", "$(1,-6)$", "$(6,1)$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Inverse Proportion Functions"} {"question": "$-\\dfrac{1}{2}$的相反数是( )", "options": ["$\\dfrac{1}{2}$", "$ 2$", "$ -2$", "$ -\\dfrac{1}{2}$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "下列计算正确的是( )", "options": ["$a^{7}\\div a^{5}=a^{2}$", "$5a-4a=1$", "$3a^{2}\\cdot 2a^{3}=6a^{6}$", "$(a-b)^{2}=a^{2}-b^{2}$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "已知点$O$是边长为$6$的等边$\\triangle ABC$的中心,点$P$在$\\triangle ABC$外,$\\triangle ABC$,$\\triangle PAB$,$\\triangle PBC$,$\\triangle PCA$的面积分别记为$S_{0}$,$S_{1}$,$S_{2}$,$S_{3}$.若$S_{1}+S_{2}+S_{3}=2S_{0}$,则线段$OP$长的最小值是( )", "options": ["$\\frac{{3\\sqrt{3}}}{2}$", "$\\frac{{5\\sqrt{3}}}{2}$", "$3\\sqrt{3}$", "$\\frac{{7\\sqrt{3}}}{2}$"], "answer": "B", "topic": "Middle--Basic Geometry--Basics of Triangles"} {"question": "$-37$的相反数是( )", "options": ["$-37$", "$37$", "$-\\frac{1}{{37}}$", "$\\frac{1}{{37}}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "在平面直角坐标系中,将点$\\left(1,1\\right)$向右平移$2$个单位后,得到的点的坐标是( )", "options": ["$(3,1)$", "$(-1,1)$", "$(1,3)$", "$(1,-1)$"], "answer": "A", "topic": "Middle--Basic Geometry--Basic Concepts of Geometry"} {"question": "为了加快构建清洁低碳、安全高效的能源体系,国家发布《关于促进新时代新能源高质量发展的实施方案》,旨在锚定到$2030$年我国风电、太阳能发电总装机容量达到$1200000000$千瓦以上的目标.数据$1200000000$用科学记数法表示为( )", "options": ["$1.2\\times 10^{10}$", "$1.2\\times 10^{9}$", "$1.2\\times 10^{8}$", "$12\\times 10^{8}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "某校九年级选出三名同学参加学校组织的\"法治和安全知识竞赛\".比赛规定,以抽签方式决定每个人的出场顺序、主持人将表示出场顺序的数字$1$,$2$,$3$分别写在$3$张同样的纸条上,并将这些纸条放在一个不透明的盒子中,搅匀后从中任意抽出一张,小星第一个抽、下列说法中正确的是( )", "options": ["小星抽到数字$1$的可能性最小", "小星抽到数字$2$的可能性最大", "小星抽到数字$3$的可能性最大", "小星抽到每个数的可能性相同"], "answer": "D", "topic": "Middle--Basic Probability and Statistics--Data Analysis"} {"question": "不等式组$\\left\\{{\\begin{array}{l}{2x+1≥3}\\\\{4x-1<7}\\end{array}}\\right.$的解集是( )", "options": ["$x\\geqslant 1$", "$x \\lt 2$", "$1\\leqslant x \\lt 2$", "$x \\lt \\frac{1}{2}$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Basic Concepts of Inequalities"} {"question": "北京冬奥会开幕式的冰雪五环由我国航天科技建造,该五环由$21000$个$LED$灯珠组成,夜色中就像闪闪发光的星星,把北京妆扮成了奥运之城,将数据$21000$用科学记数法表示为( )", "options": ["$21\\times 10^{3}$", "$2.1\\times 10^{4}$", "$2.1\\times 10^{5}$", "$0.21\\times 10^{6}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "在同一平面直角坐标系中,直线$y=-x+4$与$y=2x+m$相交于点$P\\left(3,n\\right)$,则关于$x$,$y$的方程组$\\left\\{{\\begin{array}{l}{x+y-4=0,}\\\\{2x-y+m=0}\\end{array}}\\right.$的解为( )", "options": ["$\\left\\{{\\begin{array}{l}{x=-1,}\\\\{y=5}\\end{array}}\\right.$", "$\\left\\{{\\begin{array}{l}{x=1,}\\\\{y=3}\\end{array}}\\right.$", "$\\left\\{{\\begin{array}{l}{x=3,}\\\\{y=1}\\end{array}}\\right.$", "$\\left\\{{\\begin{array}{l}{x=9,}\\\\{y=-5}\\end{array}}\\right.$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Linear Equations in Two Variables"} {"question": "平面直角坐标系中,点$M$在$y$轴的非负半轴上运动,点$N$在$x$轴上运动,满足$OM+ON=8$.点$Q$为线段$MN$的中点,则点$Q$运动路径的长为( )", "options": ["$4\\pi $", "$8\\sqrt{2}$", "$8\\pi $", "$16\\sqrt{2}$"], "answer": "B", "topic": "Middle--Basic Geometry--Basic Concepts of Geometry"} {"question": "已知抛物线$y=\\left(x-2\\right)^{2}+1$,下列结论错误的是( )", "options": ["抛物线开口向上", "抛物线的对称轴为直线$x=2$", "抛物线的顶点坐标为$\\left(2,1\\right)$", "当$x \\lt 2$时,$y$随$x$的增大而增大"], "answer": "D", "topic": "Middle--Basic Numbers and Algebra--Quadratic Functions"} {"question": "下列各数中,负数是( )", "options": ["$-1$", "$0$", "$2$", "$\\sqrt{2}$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "按一定规律排列的单项式:$x$,$3x^{2}$,$5x^{3}$,$7x^{4}$,$9x^{5}$,$\\ldots \\ldots $,第$n$个单项式是( )", "options": ["$(2n-1)x^{n}$", "$(2n+1)x^{n}$", "$(n-1)x^{n}$", "$(n+1)x^{n}$"], "answer": "A", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "在下列条件中,能够判定平行四边形$ABCD$为矩形的是( )", "options": ["$AB=AC$", "$AC\\bot BD$", "$AB=AD$", "$AC=BD$"], "answer": "D", "topic": "Middle--Basic Geometry--Quadrilaterals"} {"question": "$5G$应用在福建省全面铺开,助力千行百业迎\"智\"变.截止$2021$年底,全省$5G$终端用户达$1397.6$万户.数据$13976000$用科学记数法表示为( )", "options": ["$13976\\times 10^{3}$", "$1397.6\\times 10^{4}$", "$1.3976\\times 10^{7}$", "$0.13976\\times 10^{8}$"], "answer": "C", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"} {"question": "已知关于$x$的方程$x^{2}+mx+3=0$的一个根为$x=1$,则实数$m$的值为( )", "options": ["$4$", "$-4$", "$3$", "$-3$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "在多项式$x-y-z-m-n$中任意加括号,加括号后仍只有减法运算,然后按给出的运算顺序重新运算,称此为\"加算操作\".例如:$\\left(x-y\\right)-\\left(z-m-n\\right)=x-y-z+m+n$,$x-y-\\left(z-m\\right)-n=x-y-z+m-n$,$\\ldots $.\n下列说法:\n①至少存在一种\"加算操作\",使其运算结果与原多项式相等;\n②不存在任何\"加算操作\",使其运算结果与原多项式之和为$0$;\n③所有可能的\"加算操作\"共有$8$种不同运算结果.\n其中正确的个数是( )", "options": ["$0$", "$1$", "$2$", "$3$"], "answer": "D", "topic": "Middle--Basic Numbers and Algebra--Polynomials and Factorization"} {"question": "$-7$的相反数是( )", "options": ["$-7$", "$7$", "$\\frac{1}{7}$", "$-\\frac{1}{7}$"], "answer": "B", "topic": "Middle--Basic Numbers and Algebra--Real Numbers"}