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            • 1.

              在空间四边形\(OABC\)中,\(\overrightarrow{OA}=a\),\(\overrightarrow{OB}=b\),\(\overrightarrow{OC}=c\),点\(M\)在\(OA\)上,且\(OM=2MA\),\(N\)为\(BC\)的中点,给出以下向量\(;\)其中与\(\overrightarrow{MN}\)平行的向量是________\((\)只填相应序号即可\()\).

              \(①3a-4b+3c\);\(②-4a+3b+3c\);\(③3a+3b-4c\);\(④\dfrac{4}{3}a-b-c\).

            • 2.

              如图所示,空间四边形\(OABC\)中,\(\overrightarrow{OA}=a\),\(\overrightarrow{OB}=b\),\(\overrightarrow{OC}=c\),点\(M\)在\(\overrightarrow{OA}\)上,且\(\overrightarrow{OM}=2\overrightarrow{MA}\),\(N\)为\(BC\)的中点,\(\overrightarrow{MN}=xa+yb+zc\),则\(x\),\(y\),\(z\)分别为


              A.\(\dfrac{1}{2}\),\(-\dfrac{2}{3}\),\(\dfrac{1}{2}\)
              B.\(-\dfrac{2}{3}\),\(\dfrac{1}{2}\),\(\dfrac{1}{2}\)
              C.\(\dfrac{1}{2}\),\(\dfrac{1}{2}\),\(-\dfrac{2}{3}\)
              D.\(\dfrac{2}{3}\),\(\dfrac{2}{3}\),\(-\dfrac{1}{2}\)
            • 3. 如图所示空间四边形\(ABCD\),连接\(AC\)、\(BD\),设\(M\)、\(G\)分别是\(BC\)、\(CD\)的中点,则\( \overrightarrow{MG}- \overrightarrow{AB}+ \overrightarrow{AD}\)等于\((\)  \()\)
              A.\( \dfrac {3}{2} \overrightarrow{DB}\)
              B.\(3 \overrightarrow{MG}\)
              C.\(3 \overrightarrow{GM}\)
              D.\(2\) \( \overrightarrow{MG}\)
            • 4.

              已知向量\(p\)在基底\(\{a,b,c\}\)下的坐标为\((8,6,4)\),其中\(a=i+j\),\(b=j+k\),\(c=k+i\),则向量\(p\)在基底\(\{i,j,k\}\)下的坐标是(    )

              A.\((12,14,10)\)
              B.\((10,12,14)\)
              C.\((14,12,10)\)
              D.\((4,3,2)\)
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