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            • 1.

              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.\(4\)
            • 2.

              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.\( \dfrac{3}{2} \overrightarrow{a}+ \dfrac{1}{2} \overrightarrow{b}+ \dfrac{1}{2} \overrightarrow{c} \)
            • 3.

              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__________

            • 4.

              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.\(\left( \left. \dfrac{2}{3}, \dfrac{2}{3}, \dfrac{2}{3} \right. \right)\)
            • 5. 给出下列命题中所有正确命题的序号为_____.

              \(①\)已知\( \overrightarrow{a} ⊥ \overrightarrow{b} \),则\( \overrightarrow{a} ⋅( \overrightarrow{b} + \overrightarrow{c} )+ \overrightarrow{c} ⋅( \overrightarrow{b} - \overrightarrow{a} )= \overrightarrow{b} ⋅ \overrightarrow{c} \);

              \(②A\)、\(B\)、\(M\)、\(N\)为空间四点,若\( \overrightarrow{BA}\;, \overrightarrow{BM}\;, \overrightarrow{BN} \)不构成空间的一个基底,则\(A\)、\(B\)、\(M\)、\(N\)共面;

              \(③\)已知\( \overrightarrow{a} ⊥ \overrightarrow{a} \),则\( \overrightarrow{a} \),\( \overrightarrow{b} \)与任何向量不构成空间的一个基底;

              \(④\)已知\(\{ \overrightarrow{a} , \overrightarrow{b} , \overrightarrow{c} \}\)是空间的一个基底,则基向量\( \overrightarrow{a} \),\( \overrightarrow{b} \)可以与向量\( \overrightarrow{π} = \overrightarrow{a} + \overrightarrow{c} \)构成空间另一个基底.

            • 6.

              \((1)\)某校高中生共有\(900\)人,其中高一年级\(300\)人,高二年级\(200\)人,高三年级\(400\)人,现采用分层抽样法抽取一个容量为\(45\)的样本,那么从高二年级抽取的人数为__        ___

              \((2)\)如图所示,三棱锥\(O-ABC\)中,\( \overset{⇀}{OA}= \overset{⇀}{a} \),\( \overset{⇀}{OB}= \overset{⇀}{b} \),\( \overset{⇀}{OC}= \overset{⇀}{c} \),点\(M\)在棱\(OA\)上,且\(OM=2MA\),\(N\)为\(BC\)中点,则\( \overset{⇀}{MN}= \)__        ___\(.(\)用\( \overset{⇀}{a}, \overset{⇀}{b}, \overset{⇀}{c} \)表示\()\)

              \((3)\)生活中常用的十二进位制,如一年有\(12\)个月,时针转一周为\(12\)个小时,等等,就是逢\(12\)进\(1\)的计算制,现采用数字\(0~9\)和字母\(A\)、\(B\)共\(12\)个计数符号,这些符号与十进制的数的对应关系如下表:例如用十二进位制表示\(A+B=19\),照此算法在十二进位制中运算\(A×B=\)__        ___

              十二进制

              \(0\)

              \(1\)

              \(2\)

              \(3\)

              \(4\)

              \(5\)

              \(6\)

              \(7\)

              \(8\)

              \(9\)

              \(A\)

              \(B\)

              十进制

              \(0\)

              \(1\)

              \(2\)

              \(3\)

              \(4\)

              \(5\)

              \(6\)

              \(7\)

              \(8\)

              \(9\)

              \(10\)

              \(11\)

              \((4)\)底面为正方形的四棱锥\(S-ABCD\),且\(SD\bot \)平面\(ABCD\),\(SD=\sqrt{2}\),\(AB=1\),线段\(SB\)上一\(M\)点满足\(\dfrac{SM}{MB}=\dfrac{1}{2}\),\(N\)为线段\(CD\)的中点,\(P\)为四棱锥\(S-ABCD\)表面上一点,且\(DM\bot PN\),则点\(P\)形成的轨迹的长度为 __        ___

            • 7.

              在平行六面体 \(ABCD\)\(−\) \(EFGH\)中,若\({\,\!} \overset{→}{AG}=2x \overset{→}{AB}+3y \overset{→}{BC}+3z \overset{→}{HD} \),则 \(x\)\(+\) \(y\)\(+\) \(z\)等于\((\) \()\)

              A.\( \dfrac{7}{6}\)
              B.\( \dfrac{2}{3}\)
              C.\( \dfrac{5}{6}\)
              D.\( \dfrac{1}{2}\)
            • 8.

              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.\(2 \sqrt{3}\)
            • 9.

              在长方体\(ABCD-A_{1}B_{1}C_{1}D_{1}\)中,\(A_{1}A=3\),\(AB=2\),若棱\(AB\)上存在点\(P\),使得\(D_{1}P⊥PC\),则棱\(AD\)的长的取值范围是________.

            • 10.

              在四面体\(ABCD\)中,\(E\),\(G\)分别是\(CD\),\(BE\)的中点,若空间向量\( \overset{→}{AG}=x \overset{→}{AB}+y \overset{→}{AD}+z \overset{→}{AC} \),则\(x+y+z=\)(    )

              A.\( \dfrac{1}{3} \)
              B.\( \dfrac{1}{2} \)
              C.\(1\)
              D.\(2\)
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