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            • 1.
              \(E\),\(F\)分别为正方形\(ABCD\)的边\(AD\)和\(AB\)的中点,则\( \overrightarrow{EB}+ \overrightarrow{FD}=(\)  \()\)
              A.\( \overrightarrow{AC}\)
              B.\( \dfrac {1}{2} \overrightarrow{AC}\)
              C.\( \overrightarrow{BD}\)
              D.\( \dfrac {1}{2} \overrightarrow{BD}\)
            • 2.
              向量\( \overrightarrow{e_{1}}=(1,2)\),\( \overrightarrow{e_{2}}=(3,4)\),且\(x\),\(y∈R\),\(x \overrightarrow{e_{1}}+y \overrightarrow{e_{2}}=(5,6)\),则\(x-y=(\)  \()\)
              A.\(3\)
              B.\(-3\)
              C.\(1\)
              D.\(-1\)
            • 3.
              已知点\(P\)是\(\triangle ABC\)所在平面内一点,满足\( \overrightarrow{PA}+ \overrightarrow{PB}+ \overrightarrow{PC}= \overrightarrow{0}\),从\(\triangle ABC\)内任取一点\(Q\),则点\(Q\)在\(\triangle PBC\)内部的概率为\((\)  \()\)
              A.\( \dfrac {1}{4}\)​
              B.\( \dfrac {1}{3}\)
              C.\( \dfrac {1}{2}\)
              D.\( \dfrac {2}{3}\)
            • 4.
              \(O\)是\(\triangle ABC\)所在平面内一点,动点\(P\)满足\( \overrightarrow{OP}= \overrightarrow{OA}+λ( \dfrac { \overrightarrow{AB}}{| \overrightarrow{AB}|\sin B}+ \dfrac { \overrightarrow{AC}}{| \overrightarrow{AC}|\sin C})(λ∈(0,+∞))\),则动点\(P\)的轨迹一定通过\(\triangle ABC\)的\((\)  \()\)
              A.内心
              B.重心
              C.外心
              D.垂心
            • 5.
              在\(\triangle ABC\)中,\(∠A=120 ^{\circ} , \overrightarrow{AB}\cdot \overrightarrow{AC}=-3\),点\(G\)是\(\triangle ABC\)的重心,则\(| \overrightarrow{AG}|\)的最小值是\((\)  \()\)
              A.\( \dfrac {2}{3}\)
              B.\( \dfrac { \sqrt {6}}{3}\)
              C.\( \dfrac { \sqrt {2}}{3}\)
              D.\( \dfrac {5}{3}\)
            • 6.

              已知\(D\),\(E\),\(F\)分别是\({\triangle }{ABC}\)的边\(AB\),\(BC\),\(CA\)的中点,则下列等式中不正确的是\(({  })\)

              A.\(\overrightarrow{{FD}}{+}\overrightarrow{{DA}}{=}\overrightarrow{{FA}}\)
              B.\(\overrightarrow{{FD}}{+}\overrightarrow{{DE}}{+}\overrightarrow{{EF}}{=}\overrightarrow{0}\)
              C.\(\overrightarrow{{DE}}{+}\overrightarrow{{DA}}{=}\overrightarrow{{EC}}\)
              D.\(\overrightarrow{{DA}}{+}\overrightarrow{{DE}}{=}\overrightarrow{{FD}}\)
            • 7.
              如图,向量\(a-b\)等于\((\)  \()\)
              A.\(-4e_{1}-2e_{2}\)
              B.\(-2e_{1}-4e_{2}\)
              C.\(e_{1}-3e_{2}\)
              D.\(3e_{1}-e_{2}\)
            • 8.

              已知\(\left| \overrightarrow{a}\right|=4 \),\(\left| \overrightarrow{b}\right|=3 \),\(\left(2 \overrightarrow{a}-3 \overrightarrow{b}\right)·\left(2 \overrightarrow{a}+ \overrightarrow{b}\right)=61 \).

              \((\)Ⅰ\()\)求\( \overrightarrow{a}· \overrightarrow{b} \)的值,并求\( \overrightarrow{a} \)与\( \overrightarrow{b} \)的\(jiajiao\)夹角; 

              \((\)Ⅱ\()\)求\(\left| \overrightarrow{a}+ \overrightarrow{b}\right| \)的值.

            • 9.

              如图,点\(P\)为平行四边形\(ABCD\) 的边\(BC\)的中点,记\(\overrightarrow{AB}=a,\overrightarrow{BC}=b\),则(    )

              A.\(\overrightarrow{AP}=a+\dfrac{1}{2}b\)
              B.\(\overrightarrow{AP}=\dfrac{1}{2}a+b\)
              C.\(\overrightarrow{AP}=a-\dfrac{1}{2}b\)
              D.\(\overrightarrow{AP}=-\dfrac{1}{2}a+b\)
            • 10.

              设\(A\),\(B\),\(C\)是半径为\(1\)的圆\(O\)上的三点,\(\overrightarrow{OA}\bot \overrightarrow{OB}\),则\((\overrightarrow{OC}-\overrightarrow{OA})\cdot (\overrightarrow{OC}-\overrightarrow{OB})\)的最大值是

              A.\(1+\sqrt{2}\)
              B.\(1-\sqrt{2}\)
              C.\(\sqrt{2}-1\)
              D.\(1\)
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