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            • 1.

              已知空间四边形\(OABC\),其对角线为\(OB\),\(AC\),\(M\),\(N\)分别是\(OA\),\(CB\)的中点,点\(G\)在线段\(MN\)上,且使\(MG=2GN\),用向量\( \overrightarrow{OA}, \overrightarrow{OB}, \overrightarrow{OC} \)表示向量\( \overrightarrow{OG} \)是\((\) \()\)

              A.\( \overrightarrow{OG}= \dfrac{1}{6} \overrightarrow{OA}+ \dfrac{1}{3} \overrightarrow{OB}+ \dfrac{1}{3} \overrightarrow{OC} \)
              B.\( \overrightarrow{OG}= \dfrac{1}{6} \overrightarrow{OA}+ \dfrac{1}{3} \overrightarrow{OB}+ \dfrac{2}{3} \overrightarrow{OC} \)
              C.\( \overrightarrow{OG}= \overrightarrow{OA}+ \dfrac{2}{3} \overrightarrow{OB}+ \dfrac{2}{3} \overrightarrow{OC} \)
              D.\( \overrightarrow{OG}= \dfrac{1}{2} \overrightarrow{OA}+ \dfrac{2}{3} \overrightarrow{OB}+ \dfrac{2}{3} \overrightarrow{OC} \)
            • 2.

              如图,已知平行六面体\(ABCD-A_{1}B_{1}C_{1}D_{1}\)中,底面\(ABCD\)是边长为\(1\)的正方形,\(AA_{1}=2\),\(∠A_{1}AB=∠A_{1}AD=120^{\circ}\) ,则线段\(AC_{1}\)的长为__________

            • 3.

              设\(O-ABC\)是正三棱锥,\(G_{1}\)是\(\triangle ABC\)的重心,\(G\)是\(OG_{1}\)上的一点,且\(OG=3GG_{1}\),若\(\overrightarrow{OG}=x\overrightarrow{OA}+y\overrightarrow{OB}+z\overrightarrow{OC}\),则\((x,y,z)\)为

              A.\(\left( \left. \dfrac{1}{4}, \dfrac{1}{4}, \dfrac{1}{4} \right. \right)\)
              B.\(\left( \left. \dfrac{3}{4}, \dfrac{3}{4}, \dfrac{3}{4} \right. \right)\)

              C.\(\left( \left. \dfrac{1}{3}, \dfrac{1}{3}, \dfrac{1}{3} \right. \right)\)
              D.\(\left( \left. \dfrac{2}{3}, \dfrac{2}{3}, \dfrac{2}{3} \right. \right)\)
            • 4.
              如图,\(M\)、\(N\)分别是四面体\(OABC\)的棱\(AB\)与\(OC\)的中点,已知向量\( \overrightarrow{MN}=x \overrightarrow{OA}+y \overrightarrow{OB}+z \overrightarrow{OC}\),则\(xyz=\) ______ .
            • 5. 给出下列命题中所有正确命题的序号为_____.

              \(①\)已知\( \overrightarrow{a} ⊥ \overrightarrow{b} \),则\( \overrightarrow{a} ⋅( \overrightarrow{b} + \overrightarrow{c} )+ \overrightarrow{c} ⋅( \overrightarrow{b} - \overrightarrow{a} )= \overrightarrow{b} ⋅ \overrightarrow{c} \);

              \(②A\)、\(B\)、\(M\)、\(N\)为空间四点,若\( \overrightarrow{BA}\;, \overrightarrow{BM}\;, \overrightarrow{BN} \)不构成空间的一个基底,则\(A\)、\(B\)、\(M\)、\(N\)共面;

              \(③\)已知\( \overrightarrow{a} ⊥ \overrightarrow{a} \),则\( \overrightarrow{a} \),\( \overrightarrow{b} \)与任何向量不构成空间的一个基底;

              \(④\)已知\(\{ \overrightarrow{a} , \overrightarrow{b} , \overrightarrow{c} \}\)是空间的一个基底,则基向量\( \overrightarrow{a} \),\( \overrightarrow{b} \)可以与向量\( \overrightarrow{π} = \overrightarrow{a} + \overrightarrow{c} \)构成空间另一个基底.

            • 6.

              三棱锥\(A—BCD\)中,\(AB=AC=AD=2\),\(∠BAD=90^{\circ}\),\(∠BAC=60^{\circ}\),则\(\overrightarrow{AB}·\overrightarrow{CD}\)等于   (    ).

              A.\(-2\)                     
              B.\(2\)

              C.\(-2 \sqrt{3}\)
              D.\(2 \sqrt{3}\)
            • 7.

              \((1)\)双曲线\(\dfrac{{{x}^{2}}}{{{a}^{2}}}-\dfrac{{{y}^{2}}}{{{b}^{2}}}=1(a > 0,b > 0)\)的离心率为\(\sqrt{3}\),则其渐近线方程为________________;

              \((2)\)在正方体\(ABCD-{{A}_{1}}{{B}_{1}}{{C}_{1}}{{D}_{1}}\)中,点\(E\),\(F\)分别是底面\({{A}_{1}}{{B}_{1}}{{C}_{1}}{{D}_{1}}\)和侧面\(C{{C}_{1}}{{D}_{1}}D\)的中心,若\(\overrightarrow{EF}+\lambda \overrightarrow{{{A}_{1}}D}=\overrightarrow{0}(\lambda \in R)\),则\(\lambda =\)_________;


              \((3)\) 已知\(|AB|=4\),点\(P\)在\(A\)、\(B\)所在的平面内运动且保持\(|PA|+|PB|=6\),则\(|PA|\)的最大值和最小值分别是_____和______;

              \((4)\)已知双曲线\(\dfrac{{{x}^{2}}}{{{a}^{2}}}-\dfrac{{{y}^{2}}}{{{b}^{2}}}=1(a > 0,b > 0)\)的左、右焦点分别为\({{F}_{1}}(-c,0)\),\({{F}_{2}}(c,0).\)若双曲线上存在点\(P\)使得\(\dfrac{\sin \angle P{{F}_{1}}{{F}_{2}}}{\sin \angle P{{F}_{2}}{{F}_{1}}}=\dfrac{a}{c}\),则该双曲线的离心率\(e\)的取值范围是_______________.

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