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Question 1 · Free response · 中档
(5分)已知集合 $\cdot A = \{ { \bf x } | { \bf x } < 2 \}$ ${ \mathsf { B } } = \left\{ { \mathsf { x } } \mid 3 ~ - ~ 2 { \mathsf { x } } { > } 0 \right\}$ ,则( A $A \cap B = \{ x | x < \frac { 3 } { 2 } \}$ B $\mathsf { A } \cap \mathsf { B } { = } \emptyset$ C $A \cup B = \{ x | x < \frac { 3 } { 2 } \}$ } D $A \cup \mathsf { B } { = } \mathsf { R }$
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Question 2 · Free response · 中档
(5分)为评估一种农作物的种植效果,选了n块地作试验田.这n块地的亩产量(单位:kg)分别是 $\mathbf { \boldsymbol { x } } _ { 1 } , \mathbf { \boldsymbol { x } } _ { 2 } , \dots , \mathbf { \boldsymbol { x } } _ { \mathrm { { n } } }$ ,下面给出的指标中可以用来评估这种农作物亩产量稳定程度的是( )A $\mathsf { x } _ { 1 } , \mathsf { x } _ { 2 } , \ldots , \mathsf { x } _ { \mathsf { n } }$ 的平均数 B $\mathsf { x } _ { 1 } , \mathsf { x } _ { 2 } , \ldots , \mathsf { x } _ { \mathsf { n } }$ 的标准差C $\mathsf { x } _ { 1 } , \mathsf { x } _ { 2 } , \ldots , \mathsf { x } _ { \mathsf { n } }$ 的最大值 D. $\mathsf { x } _ { 1 } , \mathsf { x } _ { 2 } , \ldots , \mathsf { x } _ { \mathsf { n } }$ 的中位数
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Question 3 · Single choice · 中档
A. i(1+i)<sup>2</sup> B. i<sup>2</sup>(1﹣i) C. (1+i)<sup>2</sup> D. i(1+i)
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Question 4 · Free response · 中档
(5分)如图,正方形ABCD内的图形来自中国古代的太极图.正方形内切圆中的黑色部分和白色部分关于正方形的中心成中心对称.在正方形内随机取一点,则此点取自黑色部分的概率是( )
A $\frac { 1 } { 4 }$ B $\frac { \pi } { 8 }$ C $\frac { 1 } { 2 }$ D $\frac { \pi } { 4 }$
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Question 5 · Free response · 中档
(5分)已知F是双曲线C: $x ^ { 2 } - \frac { y ^ { 2 } } { 3 } = 1$ 的右焦点,P是C上一点,且PF与x轴垂直,点A的坐标是(1,3),则 $\triangle A P F$ 的面积为( )A $\frac 1 3$ B $\frac { 1 } { 2 }$ C $\frac { 2 } { 3 }$ D $\frac { 3 } { 2 }$
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Question 7 · Single choice · 中档
(5分)设$x$,$y$满足约束条件$\begin{cases}x+3y\leqslant3\\x-y\geqslant1\\y\geqslant0\end{cases}$,则$z=x+y$的最大值为( )
A. 0 B. 1 C. 2 D. 3
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Question 8 · Free response · 中档
(5分)函数 $\mathsf { y } = \frac { \mathsf { s i n 2 x } } { 1 - \mathsf { c o s x } }$ 的部分图象大致为( )
A
B
C
D
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Question 9 · Single choice · 中档
(5分)已知函数f $( x ) = \ln x + \ln ( 2 - x )$ ,则( )
A. f(x)在(0,2)单调递增 B. f(x)在(0,2)单调递减 C. $y=f$(x)的图象关于直线$x=1$对称 D. $y=f$(x)的图象关于点(1,0)对称
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Question 11 · Free response · 中档
(5分) $\triangle A B C$ 的内角A,B,C的对边分别为a,b,c,已知sinB+sinA(sinC$- \cos C ) = 0 , \mathtt { a } = 2$ $\mathsf { c } { = } \sqrt { 2 } ,$ ,则C=( )A $\frac { \pi } { 1 2 }$ B $\frac { \pi } { 6 }$ C $\frac { \pi } { 4 }$ D $\frac { \pi } { 3 }$
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Question 12 · Free response · 中档
(5分)设A,B是椭圆C: $\frac { \mathbf { x } ^ { 2 } } { 3 } + \frac { \mathbf { y } ^ { 2 } } { \mathrm { ~ m ~ } } = 1$ 长轴的两个端点,若C上存在点M满足∠ $A M B = 1 2 0 ^ { \circ }$ ,则m的取值范围是( ) A $\left( 0 , \ 1 \right] \cup \left[ 9 , \ + _ { \infty } \right)$ B.(0, $\sqrt { 3 } ] \cup [ 9 , ~ + \infty )$ C $\left( 0 , \ 1 \right] \cup \left[ 4 , \ + \infty \right)$ D.(0, $\sqrt { 3 } ] \cup [ 4 , ~ + \infty )$
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Question 13 · Fill in the blank · 中档
(5分)已知向量 $\vec{a}=(-1,\ 2)$,$\vec{b}=(m,\ 1)$,若向量 $\vec{a}+\vec{b}$ 与 $\vec{a}$ 垂直,则 $m = \underline{\quad\quad}$.
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 √ ≤ ≥ ∞ ∈ ∴
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Question 14 · Free response · 中档
(5分)曲线 $y = x ^ { 2 } + \frac { 1 } { \frac { x } { \cdot } }$ 在点(1,2)处的切线方程为 $x - y + 1 = 0$
Answer key $x - y + 1 = 0$
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Question 15 · Fill in the blank · 中档
(5分)已知$\alpha\in\left(0,\frac{\pi}{2}\right)$,$\tan\alpha=2$,则$\cos\left(\alpha-\frac{\pi}{4}\right)=$____.
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 √ ≤ ≥ ∞ ∈ ∴
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Answer key $\frac{3\sqrt{10}}{10}$
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Question 16 · Free response · 中档
(5分)已知三棱锥S﹣ABC的所有顶点都在球O的球面上,SC是球O的直径.若平面SCA⊥平面SCB,$SA=AC$,$SB=BC$,三棱锥S﹣ABC的体积为9,则球O的表面积为 36π
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Question 17 · Free response · 中档
(12分)记$S_n$为等比数列$\{a_n\}$的前$n$项和.已知$S_2=2$,$S_3=-6$. (1)求$\{a_n\}$的通项公式; (2)求$S_n$,并判断$S_{n+1}$,$S_n$,$S_{n+2}$是否成等差数列.
Answer key (1)$a_n=(-2)^n$;(2)$S_n=-\dfrac{1}{3}\left[2+(-2)^{n+1}\right]$,$S_{n+1}$,$S_n$,$S_{n+2}$成等差数列
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Question 18 · Free response · 中档
(12分)如图,在四棱锥P﹣ABCD中,AB∥CD,且 $\angle B A P = \angle C D P = 9 0 ^ { \circ }$
(1)证明:平面PAB⊥平面PAD;
(2)若 $P A = P D = A B = D C$ $\angle A P D = 9 0 ^ { \circ }$ ,且四棱锥P﹣ABCD的体积为 $\frac { 8 } { 3 }$ ,求该四棱锥的侧面积
Answer key See explanation
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Question 22 · Free response · 中档
(10分)在直角坐标系 ${ \tt x o y } \oplus { \tt \oplus } { \tt \oplus }$ ,曲线C的参数方程为 $\scriptstyle { \left\{ \begin{array} { l l } { \mathbf { x } = 3 \cos { \Theta } } \\ { \mathbf { y } = \sin { \Theta } } \end{array} \right. }$ ,(θ为参数),直线l的参数方程为 $\scriptstyle { \left\{ \begin{array} { l l } { \mathbf { x } = \mathbf { a } + 4 t } \\ { \mathbf { y } = 1 - t } \end{array} \right. }$ ,(t为参数)
(1)若a=﹣1,求C与l的交点坐标;
(2)若C上的点到l距离的最大值为 $\sqrt { 1 7 }$ ,求a
Answer key See explanation
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