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Question 1 · Free response · 中档
(5分)(2015•浙江)已知集合 $\mathrm { P } { = } \{ { \bf x } | { \bf x } ^ { 2 } - 2 { \bf x } { \geq } 0 \}$ $0 { = } \{ \mathbf { x } | 1 { < } \mathbf { x } { \leq } 2 \}$ ,则 $\begin{array} { r } { \mathrm { ~ ( ~ C _ { R } P ) ~ } \cap \mathrm { Q } = \mathrm { ~ ( ~ \qquad ~ ) ~ } } \end{array}$ A [0,1) B (0,2] C (1,2) D [1,2]
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Question 3 · Single choice · 中档
(5 分)(2015•浙江)已知$\{a_n\}$是等差数列,公差 $d$ 不为零,前 $n$ 项和是 $S_n$,若 $a_3$,$a_4$,$a_8$ 成等比数列,则( )
A. $a_1d>0,\,dS_4>0$ B. $a_1d<0,\,dS_4<0$ C. $a_1d>0,\,dS_4<0$ D. $a_1d<0,\,dS_4>0$
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Question 4 · Single choice · 中档
(5 分)(2015•浙江)命题“$\forall n\in\mathbb{N}^*$,$f(n)\in\mathbb{N}^*$且 $f(n)\le n$”的否定形式是( )
A. . $\forall n\in\mathbb{N}^*$,$f(n)\notin\mathbb{N}^*$且 $f(n)>n$ B. . $\forall n\in\mathbb{N}^*$,$f(n)\notin\mathbb{N}^*$或 $f(n)>n$ C. . $\exists n_0\in\mathbb{N}^*$,$f(n_0)\notin\mathbb{N}^*$且 $f(n_0)>n_0$ D. . $\exists n_0\in\mathbb{N}^*$,$f(n_0)\notin\mathbb{N}^*$或 $f(n_0)>n_0$
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Question 6 · Single choice · 中档
(5 分)(2015•浙江)设 A,B 是有限集,定义:d(A,B)=card(A∪B)-card(A∩B),其中 card(A)表示有限集 A 中的元素个数( ) 命题①:对任意有限集 A,B,“A≠B”是“d(A,B)>0”的充分必要条件; 命题②:对任意有限集 A,B,C,d(A,C)≤d(A,B)+d(B,C)
A. 命题①和命题②都成立 B. 命题①和命题②都不成立 C. 命题①成立,命题②不成立 D. 命题①不成立,命题②成立
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Question 9 · Fill in the blank · 中档
(6分)(2015•浙江)双曲线$\frac{x^2}{2}-y^2=1$的焦距是__________,渐近线方程是__________.
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π ² √ ≤ ≥ ∞ ∈ ∴
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Answer key $2\sqrt{3}$;$y=\pm\frac{\sqrt{2}}{2}x$
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Question 10 · Fill in the blank · 中档
(6分)(2015•浙江)已知函数$f(x)=\begin{cases}x+\dfrac{2}{x}-3,\ x\geqslant1\\ \lg(x^2+1),\ x<1\end{cases}$,则$f(f(-3))=$__________,$f(x)$的最小值是__________.
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π ² √ ≤ ≥ ∞ ∈ ∴
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Answer key $0$;$2\sqrt{2}-3$
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Question 11 · Fill in the blank · 中档
(6分)(2015•浙江)函数 $f(x)=\sin^2x+\sin x\cos x+1$ 的最小正周期是__________,单调递减区间是__________.
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π ² √ ≤ ≥ ∞ ∈ ∴
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Answer key π;$\left[k\pi+\frac{3\pi}{8},\;k\pi+\frac{7\pi}{8}\right]$($k\in\mathbb{Z}$)
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Question 12 · Fill in the blank · 中档
(4分)(2015•浙江)若 $a=\log_4 3$,则 $2^a+2^{-a}=$__________.
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π ² √ ≤ ≥ ∞ ∈ ∴
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Answer key $\frac{4\sqrt{3}}{3}$
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Question 14 · Fill in the blank · 中档
若实数 $x$,$y$ 满足 $x^2+y^2\le1$,则 $|2x+y-2|+|6-x-3y|$ 的最小值是__________.
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π ² √ ≤ ≥ ∞ ∈ ∴
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Question 15 · Fill in the blank · 中档
已知 $\vec{e}_1$,$\vec{e}_2$ 是空间单位向量,$\vec{e}_1\cdot\vec{e}_2=\dfrac{1}{2}$,若空间向量 $\vec{b}$ 满足 $\vec{b}\cdot\vec{e}_1=2$,$\vec{b}\cdot\vec{e}_2=\dfrac{5}{2}$,且对于任意 $x$,$y\in\mathbb{R}$,$$|\vec{b}-(x\vec{e}_1+y\vec{e}_2)|\ge|\vec{b}-(x_0\vec{e}_1+y_0\vec{e}_2)|=1\ (x_0,\ y_0\in\mathbb{R})$$,则 $x_0=$__________,$y_0=$__________,$|\vec{b}|=$__________.
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π ² √ ≤ ≥ ∞ ∈ ∴
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Answer key $x_0=\dfrac{3}{2}$,$y_0=2$,$|\vec{b}|=\sqrt{7}$
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