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            • 1.

              如图,在\(Δ\) \(OBC\)中, \(A\)\(BC\)的中点, \(D\)\(OB\)的靠近 \(B\)点的一个三等分点, \(CD\)\(OA\)交于点 \(E\)\(.\)若 \(\overrightarrow{OE}=\lambda \overrightarrow{OA}\),求实数 \(\lambda \)的值.


            • 2.
              已知\( \overrightarrow{a}\)、\( \overrightarrow{b}\)是两个不共线向量,设\( \overrightarrow{OA}= \overrightarrow{a}\),\( \overrightarrow{OB}=λ \overrightarrow{b}\),\( \overrightarrow{OC}=2 \overrightarrow{a}+ \overrightarrow{b}\),若\(A\),\(B\),\(C\)三点共线,则实数\(λ\)的值等于\((\)  \()\)
              A.\(1\)
              B.\(2\)
              C.\(-1\)
              D.\(-2\)
            • 3.
              如图,在平行四边形\(ABCD\)中,\(DE= \dfrac {1}{2}EC\),\(F\)为\(BC\)的中点,\(G\)为\(EF\)上的一点,且\( \overrightarrow{AG}=m \overrightarrow{AB}+ \dfrac {2}{3} \overrightarrow{AD}\),则实数\(m\)的值为\((\)  \()\)
              A.\( \dfrac {7}{9}\)
              B.\(- \dfrac {2}{9}\)
              C.\(- \dfrac {1}{9}\)
              D.\( \dfrac {5}{9}\)
            • 4.
              已知向量\( \overrightarrow{a}=(1,-1)\),\( \overrightarrow{b}=(1,1)\),\( \overrightarrow{c}=( \sqrt {2}\cos α, \sqrt {2}\sin α)(a∈R)\),实数\(m\),\(n\)满足\(m \overrightarrow{a}+n \overrightarrow{b}=2 \overrightarrow{c}\),则\((m-4)^{2}+n^{2}\)的最大值为\((\)  \()\)
              A.\(4\)
              B.\(20+8 \sqrt {2}\)
              C.\(32\)
              D.\(36\)
            • 5.
              已知直线\(PA\),\(PB\)分别与半径为\(1\)的圆\(O\)相切于点\(A\),\(B\),\(PO=2\),\( \overrightarrow{PM}=2λ \overrightarrow{PA}+(1-λ) \overrightarrow{PB}.\)若点\(M\)在圆\(O\)的内部\((\)不包括边界\()\),则实数\(λ\)的取值范围是\((\)  \()\)
              A.\((-1,1)\)
              B.\((0, \dfrac {2}{3})\)
              C.\(( \dfrac {1}{3},1)\)
              D.\((0,1)\)
            • 6.

              在边长为\(1\)的菱形\(ABCD\)中,\(∠BAD=60^{\circ}\),\(E\)是\(BC\)的中点,则\( \overset{→}{AC} ⋅ \overset{→}{AE} =\)(    )

              A.\( \dfrac{3+ \sqrt{3}}{3} \)
              B.\( \dfrac{9}{2} \)
              C.\( \sqrt{3} \)
              D.\( \dfrac{9}{4} \)
            • 7.

              已知椭圆\({C}_{1}\;:\; \dfrac{{x}^{2}}{{a}^{2}}+ \dfrac{{y}^{2}}{{b}^{2}}=1\left(a > b > 0\right) \) 经过点\(M\left(1, \dfrac{3}{2}\right) \),且其右焦点与抛物线\({C}_{2}\;:\;{y}^{2}=4x \)的焦点\(F\)重合,过点\(F\)且与坐标轴不垂直的直线与椭圆交于\(P\),\(Q\)两点.

              \((1)\)求椭圆\({C}_{1} \)的方程;

              \((2)\)设\(O\)为坐标原点,线段\(OF\)上是否存在点\(N\left(n,0\right) \),使得\( \overrightarrow{QP}· \overrightarrow{NP}= \overrightarrow{PQ}· \overrightarrow{NQ} \)?若存在,求出\(n\)的取值范围;若不存在,说明理由;

              \((3)\)过点\({P}_{0}\left(4,0\right) \)且不垂直于\(x\)轴的直线与椭圆交于\(A\),\(B\)两点,点\(B\)关于\(x\)轴的对称点为\(E\),试证明:直线\(AE\)过定点.

            • 8.

              在\(\vartriangle ABC\)中,\(\angle A=60{}^\circ \),\(AB=3\),\(AC=2.\)若\(\overrightarrow{BD}=2\overrightarrow{DC}\),\(\overrightarrow{AE}=\lambda \overrightarrow{AC}-\overrightarrow{AB}(\lambda \in R)\),且\(\overrightarrow{AD}\cdot \overrightarrow{AE}=-4\),则\(\lambda \)的值为

              A.\(\dfrac{3}{11}\)
              B.\(\dfrac{3}{5}\)
              C.\(1\)
              D.\(\dfrac{7}{13}\)
            • 9.

              如图,己知\(\left| \overrightarrow{OA} \right|=2\),\(\left| \overrightarrow{OB} \right|=2\),\(∠AOB\)为锐角,\(OM\)平分\(∠AOB\),点\(N\)为线段\(AB\)的中点,\(\left| \overrightarrow{OP} \right|=x\overrightarrow{OA}+y\overrightarrow{OB}\),若点\(P\)在阴影区域\((\)含边界\()\)内,则下列式子中满足题设条件的为________\(.(\)填序号\()\)

              \(①x\geqslant 0\),\(y\geqslant 0\);\(②x-y\geqslant 0\);\(③x-y\leqslant 0\);\(④x-2y\geqslant 0\);\(⑤2x-y\geqslant 0\).

            • 10.

              \((1)\)某工厂生产甲、乙、丙、丁四种不同型号的产品,产量分别为\(200\),\(400\),\(300\),\(100\)件\(.\)为检验产品的质量,现用分层抽样的方法从以上所有的产品中抽取\(60\)件进行检验,则应从丙种型号的产品中抽取     件\(.\)


              \((2)\)已知数列\(\{\)\(a_{n}\)\(\}\)的前\(n\)项和为\(S\)\({\,\!}_{n}\),满足\(a_{n}\)\(+3S\)\({\,\!}_{n}\)\(⋅S\)\({\,\!}_{n}\)\({\,\!}_{-1}=0(\)\(n\)\(\geqslant 2\),\(n\)\(∈N^{*})\),\(a\)\({\,\!}_{1}= \dfrac{1}{3} \),则数列\(\{\)\(a_{n}\)\(\}\)的通项公式\(a_{n}\)\(= \)______.


              \((3)\)记函数\(f(x)=\sqrt{6+x-{{x}^{2}}}\)的定义域为\(D.\)在区间\(\left[ {-}4,5 \right]\)上随机取一个数\(x\),则\(x\in D\)的概率是      


              \((4)\)在\(\triangle ABC\)中,\(∠A=60^{\circ} \),\(AB=3\),\(AC=2.\)若\( \overrightarrow{BD}=2 \overrightarrow{DC} \),\( \overrightarrow{AE}=λ \overrightarrow{AC}- \overrightarrow{AB}(λ∈R) \),且\( \overrightarrow{AD}· \overrightarrow{AE}=-4 \),则\(λ \)的值为___________.

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