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Question 1 · Free response · 中档
(5分)已知集合 $\mathbf { \delta A } { \mathbf { = } } \left\{ { \mathbf { x } } \mid { \mathbf { x } } ^ { 2 } - 2 { \mathbf { x } } - 3 { \geq } 0 \right\}$ $\mathsf { B } = \{ \mathsf { x } | - 2 \leq x < 2 \}$ ,则A∩B=( )A.[1,2) B $[ \mathbf { \nabla } - \mathbf { 1 } , \mathbf { \nabla } \mathbf { 1 } ]$ C $[ \mathbf { \partial } - 1 , \mathbf { \ } 2 )$ D $\left[ { \begin{array} { l l } { - 2 , } & { - \ 1 } \end{array} } \right]$
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Question 2 · Single choice · 中档
(5分) $\frac { ( 1 + i ) ^ { 3 } } { ( 1 - i ) ^ { 2 } } =$ )
A. 1+i B. 1﹣i C. ﹣1+i D. ﹣1﹣i
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Question 4 · Free response · 中档
(5分)已知F为双曲线C: $\mathsf { x } ^ { 2 } \cdot \mathsf { m } \mathsf { y } ^ { 2 } { = } 3 \mathsf { m } ~ ( \mathsf { m } { > } 0 )$ )的一个焦点,则点F到C的一条渐近线的距离为( )A $\sqrt { 3 }$ B.3 C $\sqrt { 3 } m$ D.3m
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Question 5 · Free response · 中档
(5分)4位同学各自在周六、周日两天中任选一天参加公益活动,则周六、周日都有同学参加公益活动的概率为( )A $\frac { 1 } { 8 }$ B $\frac { 3 } { 8 }$ C $\frac { 5 } { 8 }$ D $\frac { 7 } { 8 }$
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Question 6 · Free response · 中档
(5分)如图,圆O的半径为1,A是圆上的定点,P是圆上的动点,角x的始边为射线OA,终边为射线OP,过点P作直线OA的垂线,垂足为M,将点M到直线OP的距离表示为x的函数f(x),则$y=f$(x)在[0,π]的图象大致为()
A
B
C
D
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Question 7 · Free response · 中档
(5分)执行如图的程序框图,若输入的a,b,k分别为1,2,3,则输出的M=( )
A $\frac { 2 0 } { 3 }$ B $\frac { 7 } { 2 }$ C $\frac { 1 6 } { 5 }$ D $\frac { 1 5 } { 8 }$
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Question 8 · Free response · 中档
(5分)设 ${ \mathfrak { a } } \in \ ( 0 , \ \frac { \pi } { 2 } )$ $\beta \in ( 0 , \ \frac { \pi } { 2 } )$ ,且 $\tan \alpha = \frac { 1 + \sin \beta } { \cos \beta }$ ,则( )A $3 a - \beta = \frac { \pi } { 2 }$ B $3 \alpha + \beta = \frac { \pi } { 2 }$ C $2 \alpha - \beta = \frac { \pi } { 2 }$ D $2 \alpha + \beta = \frac { \pi } { 2 }$
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Question 9 · Single choice · 中档
(5分)不等式组 $\left\{ \begin{array} { l l } { \mathbf { x } + \mathbf { y } \geqslant 1 } \\ { \mathbf { x } - 2 \mathbf { y } \leqslant 4 } \end{array} \right.$ 的解集记为D,有下列四个命题:
p<sub>1</sub>:∀(x,y)∈D, $x ^ { + } 2 y \geq - \ 2 \ p _ { 2 }$ :∃(x,y)∈D, $x + 2 y = 2$
p<sub>3</sub>:∀(x,y)∈D, $x ^ { + } 2 y { \leq } 3 p _ { 4 }$ :∃(x,y)∈D, $\tt x ^ { + } 2 y \leq - \ 1$
其中真命题是( )
A. p<sub>2</sub>,p<sub>3</sub> B. p<sub>1</sub>,p<sub>4</sub> C. p<sub>1</sub>,p<sub>2</sub> D. $\mathsf { p } _ { 1 } , \mathsf { p } _ { 3 }$
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Question 10 · Free response · 中档
(5分)已知抛物线C: $y ^ { 2 } = 8 x$ 的焦点为F,准线为l,P是l上一点, $\mathtt { Q } \mathtt { \cdot }$ 是直线PF与C的一个交点,若 $\overrightarrow { F P } = 4 \overrightarrow { F Q }$ ,则 $\left| \mathsf { O F } \right| =$ ( )A $\frac { 7 } { 2 }$ B.3 C $\frac { 5 } { 2 }$ D.2
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Question 11 · Free response · 中档
(5分)已知函数f $( { \bf { x } } ) { \bf { \varepsilon } } = { \bf { a } } { \bf { x } } ^ { 3 } - 3 { \bf { x } } ^ { 2 } + 1$ ,若f(x)存在唯一的零点 $\mathbf { \boldsymbol { x } } _ { 0 }$ ,且 $. \mathsf { x } _ { 0 } > 0$ ,则实数a的取值范围是( )A $( 1 , \ + \infty )$ B $( 2 , ~ + \infty )$ C $\big ( \mathrm { ~ - ~ } \infty , \mathrm { ~ - ~ } 1 \big )$ D. $( \mathbf { \partial } - \infty , \mathbf { \partial } - 2 )$
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Question 12 · Free response · 中档
(5分)如图,网格纸上小正方形的边长为1,粗实线画出的是某多面体的三视图,则该多面体的各条棱中,最长的棱的长度为( )
A $6 \sqrt { 2 }$ B.6 C $4 \sqrt { 2 }$ D.4
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Question 13 · Fill in the blank · 中档
(5分)$(x - y)(x + y)^8$的展开式中$x^2y^7$的系数为______.(用数字填写答案)
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)甲、乙、丙三位同学被问到是否去过A,B,C三个城市时,
甲说:我去过的城市比乙多,但没去过B城市;
乙说:我没去过C城市;
丙说:我们三人去过同一城市;
由此可判断乙去过的城市为 A
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Question 15 · Free response · 中档
(5分)已知A,B,C为圆O上的三点,若 $\overrightarrow { A O } = \frac { 1 } { 2 } ( \overrightarrow { A B } + \overrightarrow { A C } )$ ,则 $\overrightarrow { A B } .$ 与 $\overrightarrow { \mathrm { A C } }$ 的夹角为 $90 ^ { \circ }$
Answer key $90 ^ { \circ }$
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Question 16 · Free response · 中档
(5分)已知a,b,c分别为△ABC的三个内角A,B,C的对边,a=2且(2+b) $( \sin A - \sin B ) = ( c - b ) \sin C$ ,则△ABC面积的最大值为 $\sqrt { 3 }$
Answer key ${ \sqrt { 3 } } .$
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Question 24 · Free response · 中档
若 $a>0$,$b>0$,且 $\frac{1}{a}+\frac{1}{b}=\sqrt{ab}$. (Ⅰ)求 $a^3+b^3$ 的最小值; (Ⅱ)是否存在 $a$,$b$,使得 $2a+3b=6$?并说明理由.
Answer key (Ⅰ)$4\sqrt{2}$;(Ⅱ)不存在
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