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            • 1.

              已知在平面直角坐标系\(xOy\)内,两个定点\(A(1,0)\),\(B(4,0)\),且满足\(|PB|=2|PA|\)的点\(P(x,y)\)形成的曲线记为\(Γ\).

              \((1)\)求曲线\(Γ\)的方程;

              \((2)\)过点\(B\)的直线\(l\)与曲线\(Γ\)相交于\(C\),\(D\)两点,当\(\triangle COD\)的面积最大时,求直线\(l\)的方程;

              \((3)\)设曲线\(Γ\)分别交\(x\)轴,\(y\)轴的正半轴于\(M\),\(N\)两点,点\(Q\)是曲线\(Γ\)位于第三象限内的图象上的任意一点,连接\(QN\)交\(x\)轴于点\(E\),连接\(QM\)交\(y\)轴于点\(F.\)求证:四边形\(MNEF\)的面积为定值.

            • 2.

              设椭圆\(\dfrac{{{x}^{2}}}{16}+\dfrac{{{y}^{2}}}{12}=1\)上三个点\(M\),\(N\)和\(T\),且\(M\),\(N\)在直线\(x=8\)上的射影分别为\({{M}_{1}},{{N}_{1}}\).


              \((1)\)若直线\(MN\)过原点\(O\),直线\(MT\),\(NT\)斜率分别为\({{k}_{1}},{{k}_{2}}\),求证:\({{k}_{1}}\cdot {{k}_{2}}\)为定值;


              \((2)\)若\(M\),\(N\)不是椭圆长轴的端点,点\(L\)坐标为\(\left( 3,0 \right)\),\(\Delta {{M}_{1}}{{N}_{1}}L\)与\(\Delta MNL\)面积之比为\(5\),求\(MN\)中点\(K\)的轨迹方程.

            • 3.
              已知动点\(P\)在曲线\(2x^{2}-y=0\)上移动,则点\(A(0,-1)\)与点\(P\)连线中点的轨迹方程是\((\)  \()\)
              A.\(y=2x^{2}\)
              B.\(y=8x^{2}\)
              C.\(2y=8x^{2}-1\)
              D.\(2y=8x^{2}+1\)
            • 4.

              已知动点\(P\)到\(y\)轴的距离比它到点\(M\left( -1,0 \right)\)的距离少\(1\).

              \((\)Ⅰ\()\)求动点\(P\)的轨迹方程;

              \((\)Ⅱ\()\)若直线\(l:x+y+1=0\)与动点\(P\)的轨迹交于\(A\)、\(B\)两点,求\(\triangle OAB\)的面积.

            • 5.

              已知直线\(C\)\({\,\!}_{1}\)\(\begin{cases}x=1+tcoaα, \\ y=t\sin α\end{cases} \)\((t\)为参数\()\),\(C\)\({\,\!}_{2}\)\(\begin{cases}x=\cos θ, \\ y=\sin θ\end{cases} \)\((θ\)为参数\()\).

              \((1)\)当\(α=\dfrac{\pi }{3}\)时,求\(C_{1}\)与\(C_{2}\)的直角坐标方程,以及\(C_{1}\)与\(C_{2}\)交点的极坐标\((\rho \geqslant 0,\ \theta \in [0,\ 2\pi )\);

              \((2)\)过坐标原点\(O\)作\(C_{1}\)的垂线,垂足为\(A\),\(P\)为\(OA\)中点,当\(α\)变化时,求\(P\)点的轨迹的参数方程,并指出它是什么曲线.

            • 6.

              曲线的方程为\(\sqrt{{\left(x-1\right)}^{2}+{y}^{2}} +\sqrt{{\left(x+1\right)}^{2}+{y}^{2}} =2\),若直线\(l:y=kx+1-2k\)与曲线有公共点,则\(k\)的取值范围是

              A.\(\left[ \dfrac{1}{3},1\right] \)
              B.\(\left( \dfrac{1}{3},1\right) \)
              C.\((-∞, \dfrac{1}{3}] ∪[1,+∞)\)                   
              D.\(\left(-∞, \dfrac{1}{3}\right) ∪(1,+∞)\)
            • 7.

              已知在平面直角坐标系\(xoy\)中,点\(M(\sqrt{3},0),N(-\sqrt{3},0)\),动点\(P\)满足直线\(PM\)与\(PN\)的斜率乘积为\(-\dfrac{2}{3}.(1)\)求动点\(P\)的轨迹方程;\((2)\)设动点\(P\)形成的轨迹为\(C\),\({{F}_{1}}(-1,0),{{F}_{2}}(1,0)\),连接\(P{{F}_{1}}\)与曲线\(C\)的另一个交点为\(A\),连接\(P{{F}_{2}}\)与曲线\(C\)的另一交点为\(B\),设\(\overrightarrow{P{{F}_{1}}}={{\lambda }_{1}}\overrightarrow{{{F}_{1}}A},\overrightarrow{P{{F}_{2}}}={{\lambda }_{2}}\overrightarrow{{{F}_{2}}B},\)证明:\({{\lambda }_{1}}+{{\lambda }_{2}}\)为定值.

            • 8.

              已知\(A\)、\(B\)、\(C\)为\(\triangle ABC\)的三个内角,向量\(m\)满足\(|m|=\dfrac{\sqrt{6}}{2}\),且\(m=(\sqrt{2}\sin \dfrac{B+C}{2},\cos \dfrac{B-C}{2})\),若\(A\)最大时,动点\(P\)使得\(|\overrightarrow{PB}|\)、\(|\overrightarrow{BC}|\)、\(|\overrightarrow{PC}|\)成等差数列,则\(\dfrac{|\overrightarrow{PA}|}{|\overrightarrow{BC}|}\)的最大值是

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

              在平面直角坐标系中,动点\(P\)到点\(F(1,0)\)的距离比它到\(y\)轴的距离多\(1\),记点\(P\)的轨迹为曲线\(C\),给出下列三个结论:

              \(①\)曲线\(C\)过坐标原点;

              \(②\)曲线\(C\)关于\(x\)轴对称;

              \(③\)曲线\(C\)的轨迹是抛物线.

              其中,所有正确结论的序号是_______.

            • 10.

              满足条件\(|z-2i|+|z+1|= \sqrt{5}\)的点的轨迹是\((\)  \()\)

              A.椭圆 
              B.直线
              C.线段 
              D.圆
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