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            • 1.

              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.\(2\sqrt{3}\)     
            • 2.

              如图,在三棱柱\(ABC-A_{1}B_{1}C_{1}\)中,\(M\)为\(A_{1}C_{1}\)的中点,若\(\overrightarrow{AB}=\overrightarrow{a}\),\(\overrightarrow{BC}=\overrightarrow{b}\),\(\overset{⇀}{A{A}_{1}}= \overset{⇀}{c} \),则\(\overrightarrow{BM}\)可表示为\((\)    \()\)


              A.\(-\dfrac{1}{2}\overrightarrow{a}+\dfrac{1}{2}\overrightarrow{b}+\overrightarrow{c}\)



              B.\(\dfrac{1}{2}\overrightarrow{a}+\dfrac{1}{2}\overrightarrow{b}+\overrightarrow{c}\)



              C.\(-\dfrac{1}{2}\overrightarrow{a}-\dfrac{1}{2}\overrightarrow{b}+\overrightarrow{c}\)



              D.\(\dfrac{1}{2}\overrightarrow{a}-\dfrac{1}{2}\overrightarrow{b}+\overrightarrow{c}\)


            • 3.

              在平行六面体\(ABCD-A_{1}B_{1}C_{1}D_{1}\) 中,设\( \overrightarrow{A{C}_{1}}=x \overrightarrow{AB}+2y \overrightarrow{BC}+3z \overrightarrow{C{C}_{1}} \),则\(x{+}y{+}z=(\)     \()\)

              A.\( \dfrac{2}{3}\)
              B.\( \dfrac{5}{6}\)              
              C.\( \dfrac{11}{6}\)            
              D.\( \dfrac{7}{6}\)
            • 4.

              给出以下命题,其中真命题的个数是

              \(①\)若“\((\neg p)\)或\(q\)”是假命题,则“\(p\)且\((\neg q)\)”是真命题

              \(②\)命题“若\(a+b\neq 5\),则\(a\neq 2\)或\(b\neq 3\)”为真命题

              \(③\)已知空间任意一点\(O\)和不共线的三点\(A\),\(B\),\(C\),若\(\overrightarrow{OP}=\dfrac{1}{6}\overrightarrow{PA}+\dfrac{1}{3}\overrightarrow{OB}+\dfrac{1}{2}\overrightarrow{OC}\),则\(P\),\(A\),\(B\),\(C\)四点共面;

              \(④\)直线\(y=k(x-3)\)与双曲线\(\dfrac{{{x}^{2}}}{{{a}^{2}}}-\dfrac{{{y}^{2}}}{{{b}^{2}}}=1\)交于\(A\),\(B\)两点,若\(|AB|=5\),则这样的直线有\(3\)条;

              A.\(1\)
              B.\(2\)
              C.\(3\)
              D.\(4\)
            • 5.

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

              给出以下命题,其中真命题的个数是

              \(①\)若“\(¬p \)或\(q\)”是假命题,则“\(p\)且\(¬q \)”是真命题

              \(②\)命题“若\(a+b\neq 5 \),则\(a\neq 2 \)或\(b\neq 3 \)”为真命题

              \(③\)已知空间任意一点\(O\)和不共线的三点\(A\),\(B\),\(C\),若\( \overrightarrow{OP}= \dfrac{1}{6} \overrightarrow{OA}+ \dfrac{1}{3} \overrightarrow{OB}+ \dfrac{1}{2} \overrightarrow{OC} \),则\(P\),\(A\),\(B\),\(C\)四点共面;

              \(④\)直线\(y=k\left(x-3\right) \)与双曲线\( \dfrac{{x}^{2}}{4}- \dfrac{{y}^{2}}{5}=1 \)交于\(A\),\(B\)两点,若\(\left|AB\right|=5 \),则这样的直线有\(3\)条;

              A.\(1\)                   
              B.\(2\)                 
              C.  \(3\)                
              D.\(4\)
            • 7.

              如图所示,在平行六面体\(ABCD-A_{1}B_{1}C_{1}D_{1}\)中,设\( \overrightarrow{A{A}_{1}}= \overrightarrow{a} \),\( \overrightarrow{AB}= \overrightarrow{b} \),\( \overrightarrow{AD}= \overrightarrow{c} \),\(M\),\(N\),\(P\)分别是\(AA_{1}\),\(BC\),\(C_{1}D_{1}\)的中点,则\( \overrightarrow{MP}+ \overrightarrow{N{C}_{1}}= =(\)  \()\)


              A.\( \dfrac{3}{2} \overrightarrow{a}+ \dfrac{1}{2} \overrightarrow{b}+ \dfrac{3}{2} \overrightarrow{c} \) 
              B.\( \overrightarrow{a}+ \dfrac{1}{2} \overrightarrow{c} \)          
              C.\( \dfrac{1}{2} \overrightarrow{a}+ \dfrac{1}{2} \overrightarrow{b}+ \overrightarrow{c} \)
              D.\( \dfrac{3}{2} \overrightarrow{a}+ \dfrac{1}{2} \overrightarrow{b}+ \dfrac{1}{2} \overrightarrow{c} \)
            • 8.

              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__________

            • 9.

              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.\(\left( \left. \dfrac{2}{3}, \dfrac{2}{3}, \dfrac{2}{3} \right. \right)\)
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