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Question 1 · Free response · 中档
(5分)已知集合 $\mathsf { A } \mathbf { = } \left\{ \mathbf { \mathsf { x } } \mid \mathbf { \mathsf { x } } \right.$ 是平行四边形}, ${ \sf B } = \left\{ { \sf x } \left| \sf x \right. \right.$ 是矩形}, ${ \sf C } = \left\{ { \sf x } \left| \sf x \right. \right.$ 是正方形}${ \sf D } = \left\{ { \sf x } \left| \sf x \right. \right.$ 是菱形},则(A $\mathsf { A } \subseteq \mathsf { B }$ B.C⊆B C ${ \mathsf { D } } { \subseteq } { \mathsf { C } }$ D $\mathsf { A } \subseteq \mathsf { D }$
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Question 3 · Free response · 中档
(5分)若函数 $f ( \mathbf { x } ) = \mathbf { s i n } { \frac { \mathbf { x } + \Phi } { 3 } } ( \Phi \in [ 0 , ~ 2 \pi ] ) ,$ 是偶函数,则φ=( )A $\frac { \pi } { 2 }$ B $\frac { 2 \pi } { 3 }$ C $\frac { 3 \pi } { 2 }$ D $\frac { 5 \pi } { 3 }$
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Question 4 · Free response · 中档
(5分)已知α为第二象限角, $\sin a = \frac { 3 } { 5 }$ ,则 $\sin 2 a =$ ( )A $\frac { 2 4 } { 2 5 }$ B $\frac { 1 2 } { 2 5 }$ C $\frac { 1 2 } { 2 5 }$ D $\frac { 2 4 } { 2 5 }$
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Question 5 · Free response · 中档
(5分)椭圆的中心在原点,焦距为4,一条准线为 $J \times = - \ 4$ ,则该椭圆的方程为( )A $\frac { x ^ { 2 } } { 1 6 } + \frac { y ^ { 2 } } { 1 2 } = 1$ B $\frac { x ^ { 2 } } { 1 2 } + \frac { y ^ { 2 } } { 8 } = 1$ C $\frac { x ^ { 2 } } { 8 } + \frac { y ^ { 2 } } { 4 } = 1$ D $\frac { x ^ { 2 } } { 1 2 } + \frac { y ^ { 2 } } { 4 } = 1$
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Question 6 · Free response · 中档
(5分)已知数列 $\{ \mathsf { a } _ { \mathsf { n } } \}$ 的前n项和为 $\mid \mathsf { S } _ { \mathsf { n } } , ~ \mathsf { a } _ { 1 } \mathsf { = } 1 , ~ \mathsf { S } _ { \mathsf { n } } \mathsf { = } 2 \mathsf { a } _ { \mathsf { n } + 1 }$ ,则当 $\mathsf { n } > 1$ 时, $\mathsf { S } _ { \mathsf { n } } \mathsf { = }$ ()A $( \frac { 3 } { 2 } ) n - 1$ B $2 ^ { { \mathsf { n } } - 1 }$ C $( \frac { 2 } { 3 } ) n - 1$
$$
\frac { 1 } { 3 } ( \frac { 1 } { 2 ^ { n - 1 } } - 1 )
$$
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Question 7 · Single choice · 中档
(5分)6位选手依次演讲,其中选手甲不在第一个也不在最后一个演讲,则不同的演讲次序有( )
A. 240种 B. 360种 C. 480种 D. 720种
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Question 8 · Free response · 中档
(5分)已知正四棱柱 $\mathsf { A B C D } - \mathsf { A _ { 1 } B _ { 1 } C _ { 1 } D _ { 1 } } ^ { \mathsf { E } }$ 中, $\mathsf { A B } { = } 2$ ${ \mathsf { C C } } _ { 1 } { = } 2 { \sqrt { 2 } } ;$ ,E为 $\mathsf { C C } _ { 1 }$ 的中点,则直线 $\mathsf { A C } _ { 1 }$ 与平面BED的距离为( )A.2 B $\sqrt { 3 }$ C $\sqrt { 2 }$ D.1
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Question 9 · Free response · 中档
(5分) $\triangle A B C ^ { \sharp }$ ,AB边的高为CD,若 $\overrightarrow { C B } = \overrightarrow { a }$ $\overrightarrow { C A } = \overrightarrow { b }$ $\stackrel { } { \circ } \cdot \stackrel { } { \ b } = 0$ $\stackrel { } { \sf \bar { a } } | = 1$ $\vert \overrightarrow { b } \vert = 2$ ,则 $\overrightarrow { \mathrm { A D } } =$ )A $\frac { 1 } { 3 } \overrightarrow { \mathbf { a } } - \frac { 1 } { 3 } \overrightarrow { \mathbf { b } }$ B $\frac { 2 } { 3 } \overrightarrow { \mathbf { a } } - \frac { 2 } { 3 } \overrightarrow { \mathbf { b } }$ C $\frac { 3 } { 5 } \overrightarrow { \mathbf { a } } - \frac { 3 } { 5 } \overrightarrow { \mathbf { b } }$ D $\frac { 4 } { 5 } \overrightarrow { \mathbf { a } } - \frac { 4 } { 5 } \overrightarrow { \mathbf { b } }$
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Question 10 · Free response · 中档
(5分)已知 $\mathsf { F } _ { 1 } , \mathsf { F } _ { 2 }$ 为双曲线C: $\ x ^ { 2 } - y ^ { 2 } = 2$ 的左、右焦点,点P在C上, $\vert P F _ { 1 } \vert = 2$ $\left| \mathsf { P F } _ { 2 } \right|$ ,则 $\mathsf { c o s } \angle \mathsf { F } _ { 1 } \mathsf { P } \mathsf { F } _ { 2 } \mathbf { = }$ ( )A $\frac { 1 } { 4 }$ B. $\frac { 3 } { 5 }$ C $\frac { 3 } { 4 }$ D $\frac { 4 } { 5 }$
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Question 11 · Free response · 中档
(5分)已知 $\scriptstyle | \mathbf { x } = | { \mathsf { n } } \pi$ $\tt y = \tt l o g _ { 5 } 2$ $\boldsymbol { \mathbf { \mathit { z } } } = \boldsymbol { \mathbf { \mathit { e } } } ^ { - \frac { 1 } { 2 } }$ ,则( )A $x { < y < z }$ B ${ \boldsymbol { z } } { < } { \mathsf { x } } { < } { \mathsf { y } }$ C $z { < y < x }$ D. $\forall { < z < x }$
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Question 12 · Single choice · 中档
(5分)正方形ABCD的边长为1,点E在边AB上,点F在边BC上, $A E = B F = \frac { 1 } { 3 }$ 定点P从E出发沿直线向F运动,每当碰到正方形的边时反弹,反弹时反射角等于入射角.当点P第一次碰到E时,P与正方形的边碰撞的次数为( )
A. 8 B. 6 C. 4 D. 3
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Question 13 · Fill in the blank · 中档
(5分)$(x+\frac{1}{2x})^8$的展开式中$x^2$的系数为____.
先写答案,再对照解析 等价写法不自动判错
直接输入 Formula Chemistry
π ² √ ≤ ≥ ∞ ∈ ∴
写好了,对答案
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Question 14 · Free response · 中档
(5分)若x,y满足约束条件 $\left\{ \begin{array} { l l } { \mathbf { x } - \mathbf { y } + 1 \geqslant 0 } \\ { \mathbf { x } + \mathbf { y } - 3 \leqslant 0 } \\ { \mathbf { x } + 3 \mathbf { y } - 3 \geqslant 0 } \end{array} \right.$ 则 $z = 3 x - y$ 的最小值为 ﹣1 0
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Question 15 · Free response · 中档
(5分)当函数 $y = \mathsf { s i n x } - \sqrt { 3 } \mathsf { c o s x } \ ( 0 \leq x < 2 \pi )$ )取得最大值时, $x = - \frac { 5 \pi } { 6 } -$
Answer key $\frac { 5 \pi } { 6 }$
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Question 17 · Free response · 中档
(10分) $\triangle A B C \sharp$ ,内角A,B,C成等差数列,其对边a,b,c满足 $2 b ^ { 2 } = 3 a c$ ,求A
Answer key See explanation
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Question 18 · Free response · 中档
(12分)已知数列 $\{ \mathsf { a } _ { \mathsf { n } } \}$ 中, $\mathtt { a } _ { 1 } = 1$ ,前n项和 $S _ { \mathrm { n } } = \frac { \mathrm { n + 2 } } { 3 } \bar { \bf { a } } _ { \mathrm { n } }$
(1)求 $\mathtt { a } _ { 2 }$ , $\mathsf { a } _ { 3 } \mathsf { : }$
(2)求 $\{ \mathsf { a } _ { \mathsf { n } } \}$ 的通项公式
Answer key See explanation
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Question 20 · Free response · 中档
(12分)乒乓球比赛规则规定:一局比赛,对方比分在10平前,一方连续发球2次后,对方再连续发球两次,依次轮换.每次发球,胜方得1分,负方得0分.设在甲、乙的比赛中,每次发球,发球方得1分的概率为0.6,各次发球的胜负结果相互独立.甲、乙的一局比赛中,甲先发球
(1)求开始第4次发球时,甲、乙的比分为1:2的概率;
(2)求开始第5次发球时,甲领先得分的概率
Answer key See explanation
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Question 22 · Free response · 中档
(12分)已知抛物线C: $\forall \mathbf { \bar { \mathbf { \tau } } } \mathbf { \Psi } ( \mathbf { x } ^ { + } 1 )$ <sup>2</sup>与圆 $( \mathbf { x } - 1 ) ^ { 2 } + ( \mathbf { y } \frac { 1 } { 2 } ) ^ { 2 } = \mathbf { r } ^ { 2 } ( \mathbf { r } > 0 )$ 有一个公共点A,且在A处两曲线的切线为同一直线l
(Ⅰ)求r;
(Ⅱ)设m,n是异于l且与C及M都相切的两条直线,m,n的交点为D,求D到l 的距离
Answer key See explanation
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