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            • 1. 一个多面体的直观图及三视图如图所示,\(M\)、\(N\)分别是\(AB_{1}\)、\(A_{1}C_{1}\)的中点.

              \((1)\)求证:\(MN{⊥}AB_{1}{,}MN{/\!/}\)平面\({BC}C_{1}B_{1}\);
              \((2)\)求二面角\(A{-}BC_{1}{-}C\)的余弦值.
            • 2.

              已知向量\(a=(0,-1,1)\),\(b=(4,1,0)\),\(|λa+b|= \sqrt{29}\)且\(λ > 0\),则实数\(λ=\)________.

            • 3.

              在空间平移\(\triangle ABC\)到\(\triangle A_{1}B_{1}C_{1}(\)使\(\triangle A_{1}B_{1}C_{1}\)与\(\triangle ABC\)不共面\()\),连接对应顶点,设\(\overset{→}{A{A}_{1}}= \overset{→}{a} \),\(\overset{→}{AB}= \overset{→}{b} \),\(\overset{→}{AC}= \overset{→}{c} \),\(M\)是\(BC_{1}\)的中点,\(N\)是\(B_{1}C_{1}\)的中点,用基底\(\left\{ \overset{→}{a}, \overset{→}{b}, \overset{→}{c}\right\} \)表示向量\(\overrightarrow{AM}+\overrightarrow{AN}\)的结果是__________.

            • 4.

              已知三棱锥\(O-ABC\),点\(M\),\(N\)分别为\(AB\),\(OC\)的中点,且\(\overrightarrow{OA}=a\),\(\overrightarrow{OB}=b\),\(\overrightarrow{OC}=c\),用\(a\),\(b\),\(c\)表示\(\overrightarrow{MN}\),则\(\overrightarrow{MN}\)等于\((\)  \()\)




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

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

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

              D.\( \dfrac{1}{2}(c-a-b)\)
            • 5. 已知 \(a\)\(=(-2,1,3)\), \(b\)\(=(-1,2,1)\),若 \(a\)\(⊥( \)\(a\)\(-\) \(λb\)\()\),则实数 \(λ\)的值为(    )
              A.\(-2\)    
              B.\(- \dfrac{14}{3}\)
              C.\( \dfrac{14}{5}\)                        
              D.\(2\)
            • 6.

              \((1)\)命题\("∀{x}_{0}∈\left(0,+∞\right),\ln x+2\leqslant {e}^{{x}_{0}} "\)的否定是_______   

              \((2)\)已知函数\(f(x)=\begin{cases} & {{x}^{-{{m}^{2}}+2m+3}}(x\geqslant 1) \\ & (2m-1)x+m(x < 1) \end{cases}\)在\(R\)上是单调递增函数,则\(m\)的取值范围是__________________

              \((3)\) 如图,四面体\(ABCD\)的每条棱长都等于\(2\),点\(E\),\(F\)分别为棱\(AB\),\(AD\)的中点,则\(\left| \overrightarrow{AC}+\overrightarrow{EF} \right|=\)_____; \(\left| \overset{→}{BC}- \overset{→}{EF}\right| \) ___________;

              \((4)\)已知四棱锥\(P-ABCD\)的五个顶点都在球\(O\)的球面上,底面\(ABCD\)是矩形,平面\(PAD\)垂直于平面\(ABCD\),在\(\triangle PAD\)中,\(PA=PD=2\),\(∠APD=120^{\circ}\),\(AB=4\),则球\(O\)的表面积等于____  

            • 7.

              已知空间直角坐标系中有点\(A(-2,1,3)\),\(B(3,1,0)\),则\(|\overrightarrow{AB}|=\)________.

            • 8.

              已知\(a=(1-t,2t-1,0)\),\(b=(2,t,t)\),则\(|b-a|\)的最小值

              A.\(\sqrt{5}\)
              B.\(\sqrt{6}\)
              C.\(\sqrt{2}\)
              D.\(\sqrt{3}\)
            • 9. 如图所示,在平行六面体\(ABCD-A_{1}B_{1}C_{1}D_{1}\)中,\(M\)为\(A_{1}C_{1}\)与\(B_{1}D_{1}\)的交点\(.\)若\(\overrightarrow{AB}=a\),\(\overrightarrow{AD}=b\),\(\overrightarrow{A{{A}_{1}}}=c\),则下列向量中与\(\overrightarrow{BM}\)相等的向量是  \((\)    \()\)

              A.\(-\dfrac{1}{2}a+\dfrac{1}{2}b+c\)
              B.\(\dfrac{1}{2}a+\dfrac{1}{2}b+c\)
              C.\(-\dfrac{1}{2}a-\dfrac{1}{2}b+c\)
              D.\(\dfrac{1}{2}a-\dfrac{1}{2}b+c\)
            • 10. 已知\(A\),\(B\),\(C\)三点不共线,对平面\(ABC\)外的任一点\(O\),若点\(M\)满足\(\overrightarrow{OM}= \dfrac{1}{3}(\overrightarrow{OA}+\overrightarrow{OB}+\overrightarrow{OC}).\)

              \((1)\)判断\(\overrightarrow{MA}\),\(\overrightarrow{MB}\),\(\overrightarrow{MC}\)三个向量是否共面;

              \((2)\)判断点\(M\)是否在平面\(ABC\)内.

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