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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.
              在平行六面体\(ABCD-A_{1}B_{1}C_{1}D_{1}\)中,设\( \overrightarrow{AC_{1}}=x \overrightarrow{AB}+2y \overrightarrow{BC}+3z \overrightarrow{CC_{1}}\),则\(x+y+z\)等于\((\)  \()\)
              A.\(1\)
              B.\( \dfrac {2}{3}\)
              C.\( \dfrac {5}{6}\)
              D.\( \dfrac {11}{6}\)
            • 5.
              已知\(\{ \overrightarrow{a}, \overrightarrow{b}, \overrightarrow{c}\}\)是空间向量的一个基底,则可以与向量\( \overrightarrow{p}= \overrightarrow{a}+ \overrightarrow{b}\),\( \overrightarrow{q}= \overrightarrow{a}- \overrightarrow{b}\)构成基底的向量是\((\)  \()\)
              A.\( \overrightarrow{a}\)
              B.\( \overrightarrow{b}\)
              C.\( \overrightarrow{a}+2 \overrightarrow{b}\)
              D.\( \overrightarrow{a}+2 \overrightarrow{c}\)
            • 6.
              如图所示,在平行六面体\(ABCD-A_{1}B_{1}C_{1}D_{1}\)中,设\( \overrightarrow{AA_{1}}= \overrightarrow{a}\),\( \overrightarrow{AB}= \overrightarrow{b}\),\( \overrightarrow{AD}= \overrightarrow{c}\),\(M\),\(N\),\(P\)分别是\(AA_{1}\),\(BC\),\(C_{1}D_{1}\)的中点,则\( \overrightarrow{MP}+ \overrightarrow{NC_{1}}=(\)  \()\)
              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.\( \dfrac {3}{2} \overrightarrow{a}+ \dfrac {1}{2} \overrightarrow{b}+ \dfrac {1}{2} \overrightarrow{c}\)
            • 7.
              如图,在三棱柱\(ABC-A_{1}B_{1}C_{1}\)中,\(M\)为\(A_{1}C_{1}\)的中点,若\( \overrightarrow{AB}= \overrightarrow{a}\),\( \overrightarrow{BC}= \overrightarrow{b}\),\( \overrightarrow{AA_{1}}= \overrightarrow{c}\),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.\( \dfrac {1}{2} \overrightarrow{a}- \dfrac {1}{2} \overrightarrow{b}+ \overrightarrow{c}\)
            • 8.
              如图,已知空间四边形\(OABC\),其对角线为\(OB\)、\(AC\),\(M\)、\(N\)分别是对边\(OA\)、\(BC\)的中点,点\(G\)在线段\(MN\)上,且\( \overrightarrow{MG}=2 \overrightarrow{GN}\),现用基向量\( \overrightarrow{OA}\),\( \overrightarrow{OB}\),\( \overrightarrow{OC}\)表示向量,设\( \overrightarrow{OG}=x \overrightarrow{OA}+y \overrightarrow{OB}+z \overrightarrow{OC}\),则\(x\)、\(y\)、\(z\)的值分别是\((\)  \()\)
              A.\(x= \dfrac {1}{3}\),\(y= \dfrac {1}{3}\),\(z= \dfrac {1}{3}\)
              B.\(x= \dfrac {1}{3}\),\(y= \dfrac {1}{3}\),\(z= \dfrac {1}{6}\)
              C.\(x= \dfrac {1}{3}\),\(y= \dfrac {1}{6}\),\(z= \dfrac {1}{3}\)
              D.\(x= \dfrac {1}{6}\),\(y= \dfrac {1}{3}\),\(z= \dfrac {1}{3}\)
            • 9.
              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\(xyz=\) ______ .
            • 10.

              如图所示,空间四边形\(OABC\)中,\(\overrightarrow{OA}=a\),\(\overrightarrow{OB}=b\),\(\overrightarrow{OC}=c\),点\(M\)在\(OA\)上,且\(OM=2MA\),点\(N\)为\(BC\)的中点,则\(\overrightarrow{MN}\)等于\((\)    \()\)

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