优优班--学霸训练营 > 知识点挑题
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            • 1.

              给出以下命题,其中真命题的个数是

              \(①\)若“\((\neg p)\)或\(q\)”是假命题,则“\(p\)且\((\neg q)\)”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\(\overrightarrow{OP}=\dfrac{1}{6}\overrightarrow{PA}+\dfrac{1}{3}\overrightarrow{OB}+\dfrac{1}{2}\overrightarrow{OC}\),则\(P\),\(A\),\(B\),\(C\)四点共面;

              \(④\)直线\(y=k(x-3)\)与双曲线\(\dfrac{{{x}^{2}}}{{{a}^{2}}}-\dfrac{{{y}^{2}}}{{{b}^{2}}}=1\)交于\(A\),\(B\)两点,若\(|AB|=5\),则这样的直线有\(3\)条;

              A.\(1\)
              B.\(2\)
              C.\(3\)
              D.\(4\)
            • 2.

              已知空间四边形\(OABC\),其对角线为\(OB\),\(AC\),\(M\),\(N\)分别是\(OA\),\(CB\)的中点,点\(G\)在线段\(MN\)上,且使\(MG=2GN\),用向量\( \overrightarrow{OA}, \overrightarrow{OB}, \overrightarrow{OC} \)表示向量\( \overrightarrow{OG} \)是\((\) \()\)

              A.\( \overrightarrow{OG}= \dfrac{1}{6} \overrightarrow{OA}+ \dfrac{1}{3} \overrightarrow{OB}+ \dfrac{1}{3} \overrightarrow{OC} \)
              B.\( \overrightarrow{OG}= \dfrac{1}{6} \overrightarrow{OA}+ \dfrac{1}{3} \overrightarrow{OB}+ \dfrac{2}{3} \overrightarrow{OC} \)
              C.\( \overrightarrow{OG}= \overrightarrow{OA}+ \dfrac{2}{3} \overrightarrow{OB}+ \dfrac{2}{3} \overrightarrow{OC} \)
              D.\( \overrightarrow{OG}= \dfrac{1}{2} \overrightarrow{OA}+ \dfrac{2}{3} \overrightarrow{OB}+ \dfrac{2}{3} \overrightarrow{OC} \)
            • 3.

              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.\(4\)
            • 4.

              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.\( \dfrac{3}{2} \overrightarrow{a}+ \dfrac{1}{2} \overrightarrow{b}+ \dfrac{1}{2} \overrightarrow{c} \)
            • 5.

              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__________

            • 6.

              圆\(O\)上两点\(C\),\(D\)在直径\(AB\)的两侧\((\)如图甲\()\),沿直径\(AB\)将圆\(O\)折起形成一个二面角\((\)如图乙\()\),若\(∠DOB\)的平分线交弧\(\overline {BD} \)于点\(G\),交弦\(BD\)于点\(E\),\(F\)为线段\(BC\)的中点.

              \((\)Ⅰ\()\)证明:平面\(OGF/\!/\)平面\(CAD\);\((\)Ⅱ\()\)若二面角\(C-AB-D\)为直二面角,且\(AB=2\),\(∠CAB=45^{\circ}\),\(∠DAB=60^{\circ}\),求直线\(FG\)与平面\(BCD\)所成角的正弦值.

            • 7.
              空间四边形\(OABC\)中,\(M\),\(N\)分别是对边\(OA\),\(BC\)的中点,点\(G\)为\(MN\)中点,设\( \overrightarrow{OA}= \overrightarrow{a}\),\( \overrightarrow{OB}= \overrightarrow{b}\),\( \overrightarrow{OC}= \overrightarrow{c}\),则\( \overrightarrow{OG}\)可以用基底\(\{ \overrightarrow{a}, \overrightarrow{b}, \overrightarrow{c}\}\)表示为\((\)  \()\)
              A.\( \dfrac {1}{4} \overrightarrow{a}+ \dfrac {1}{4} \overrightarrow{b}+ \dfrac {1}{4} \overrightarrow{c}\)
              B.\( \dfrac {1}{4} \overrightarrow{a}+ \dfrac {1}{4} \overrightarrow{b}+ \dfrac {1}{3} \overrightarrow{c}\)
              C.\( \dfrac {1}{4} \overrightarrow{a}+ \dfrac {1}{4} \overrightarrow{b}+ \dfrac {1}{6} \overrightarrow{c}\)
              D.\( \dfrac {1}{4} \overrightarrow{a}+ \dfrac {1}{4} \overrightarrow{b}+ \dfrac {1}{4} \overrightarrow{c}\)
            • 8.

              如图,在三棱柱\(ABC-{{A}_{1}}{{B}_{1}}{{C}_{1}}\)中,\(M\)为\({{A}_{1}}{{C}_{1}}\)的中点,若\(\overrightarrow{AB}=\vec{a}\),\(\overrightarrow{BC}=\vec{b}\),\(\overrightarrow{A{{A}_{1}}}=\vec{c}\),则\(\overrightarrow{BM}\)可表示为\((\)  \()\)

              A.\(-\dfrac{1}{2}\vec{a}+\dfrac{1}{2}\vec{b}+\vec{c}\)
              B.\(\dfrac{1}{2}\vec{a}+\dfrac{1}{2}\vec{b}+\vec{c}\)
              C.\(-\dfrac{1}{2}\vec{a}-\dfrac{1}{2}\vec{b}+\vec{c}\)
              D.\(\dfrac{1}{2}\vec{a}-\dfrac{1}{2}\vec{b}+\vec{c}\)
            • 9. 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.

            • 10.

              \((1)\)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 __        ___

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