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            • 1.
              如图,\(D\)是\(\triangle ABC\)的边\(AB\)的中点,则向量\( \overrightarrow{CD}\)等于\((\)  \()\)
              A.\(- \overrightarrow{BC}+ \dfrac {1}{2} \overrightarrow{BA}\)
              B.\(- \overrightarrow{BC}- \dfrac {1}{2} \overrightarrow{BA}\)
              C.\( \overrightarrow{BC}- \dfrac {1}{2} \overrightarrow{BA}\)
              D.\( \overrightarrow{BC}+ \dfrac {1}{2} \overrightarrow{BA}\)
            • 2.
              边长为\(8\)的等边\(\triangle ABC\)所在平面内一点\(O\),满足\( \overrightarrow{OA}-2 \overrightarrow{OB}-3 \overrightarrow{OC}= \overrightarrow{0}\),若\(| \overrightarrow{OP}|= \sqrt {19}\),则\(|PA|\)的最大值为\((\)  \()\)
              A.\(6 \sqrt {3}\)
              B.\(2 \sqrt {19}\)
              C.\(3 \sqrt {19}\)
              D.\(4 \sqrt {19}\)
            • 3.
              已知\(\triangle ABC\)满足\( \overrightarrow{AB}^{2}= \overrightarrow{AB}\cdot \overrightarrow{AC}+ \overrightarrow{BA}\cdot \overrightarrow{BC}+ \overrightarrow{CA}\cdot \overrightarrow{CB}\),则\(\triangle ABC\)是\((\)  \()\)
              A.等边三角形
              B.锐角三角形
              C.直角三角形
              D.钝角三角形
            • 4.

              称\(d(a,b)=|a-b|\)为两个向量\(a\),\(b\)间的“距离”\(.\)若向量\(a\),\(b\)满足:\(①|b|=1\);\(②a\neq b\);\(③\)对任意的\(t∈R\),恒有\(d(a,tb)\geqslant d(a,b)\),则(    )

              A.\(a⊥b\) 
              B.\(b⊥(a-b)\)

              C.\(a⊥(a-b)\) 
              D.\((a+b)⊥(a-b)\)
            • 5.

              若\(P\)为\({\triangle }ABC\)所在平面内任一点,且满足\((\overrightarrow{{PB}}{-}\overrightarrow{{PC}}){⋅}(\overrightarrow{{PB}}{+}\overrightarrow{{PC}}{-}2\overrightarrow{{PA}}){=}0\),则\({\triangle }ABC\)的形状为\(({ }\ { })\)

              A.直角三角形                                                    
              B.等腰三角形
              C.正三角形                                                         
              D.等腰直角三角形
            • 6.

              \({\triangle }{ABC}\)所在平面上一点\(P\)满足\(\overrightarrow{{PA}}{+}\overrightarrow{{PB}}{+}\overrightarrow{{PC}}{=}\overrightarrow{{AB}}\),则\({\triangle }{PAB}\)的面积与\({\triangle }{ABC}\)的面积比为\(({  })\)

              A.\(2\):\(3\)                         
              B.\(1\):\(3\)                         
              C.\(1\):\(4\)                         
              D.\(1\):\(6\)
            • 7.

              若点\(P\left(2,1\right) \)的直线\(l\)与函数\(f\left(x\right)= \dfrac{2x+3}{2x-4} \)的图象交于\(A\)、\(B\)两点,\(O\)为坐标原点,则\(\left( \overrightarrow{OA}+ \overrightarrow{OB}\right)· \overrightarrow{OP}= \)

              A.\( \sqrt{5} \)
              B.\(2 \sqrt{5} \)
              C.\(5\)
              D.\(10\)
            • 8.

              \((1)\)计算\(\int_{{-}1}^{0}{\left( x{+}1 \right){dx}}{=}\)_________________.

              \((2)\)已知函数\(f\left( x \right){=}2\sin{\left( \omega x{+}\dfrac{\pi}{3} \right)\ \left( \omega{ > }0 \right){,}A{,}B}\)是函数\(y{=}f(x)\)图象上相邻的最高点和最低点,若\(\left| {AB} \right|{=}2\sqrt{5}\),则\(f\left( 1 \right){=}\)_______________.

              \((3)\)已知双曲线\(\dfrac{x^{2}}{a^{2}}{-}\dfrac{y^{2}}{b^{2}}{=}1(a{ > }0{,}b{ > }0)\)的一条渐近线方程是\(y{=}2x\),它的一个焦点与抛物线\(y^{2}{=}20x\)的焦点相同,则双曲线的方程是_____________________.

              \((4)\)如图,在平面四边形\({\ ABCD\ }\)中,\(AB{⊥}BC\),\(AD{⊥}CD\),\(\ {∠}BAD\ {=}\ 120{^{\circ}}\),\(\ AB\ {=}\ AD\ {=}\ 2.\)若点\(E\)为边\({CD}\)上的动点,则\(\overrightarrow{{AE}}{⋅}\overrightarrow{{BE}}\)的最小值为________________.

            • 9.

              \((1)\)已知向量\(\overrightarrow{a},\overrightarrow{b}\)的夹角为\(60^{\circ}\),\(\left| \overrightarrow{a} \right|=2,\left| \overrightarrow{b} \right|=1\),则\(\left| \overrightarrow{a}+2\overrightarrow{b} \right|=\)_____.

              \((2)\)已知双曲线\(C\):\(\dfrac{{{x}^{2}}}{{{a}^{2}}}-\dfrac{{{y}^{2}}}{{{b}^{2}}}=1(a > 0,b > 0)\)的右顶点为\(A\),以\(A\)为圆心,\(b\)为半径作圆\(A\),圆\(A\)与双曲线\(C\)的一条渐近线交于\(M\),\(N\)两点\(.\)若\(∠MAN=60^{\circ}\),则\(C\)的离心率为_____.

              \((3)\)在\(\triangle ABC\)中,\(AB\)边上的中线\(CO=4\),若动点\(P\)满足\(\overrightarrow{PA}={{\sin }^{2}}\dfrac{\theta }{2}\overrightarrow{OA}+{{\cos }^{2}}\dfrac{\theta }{2}\overrightarrow{CA}(\theta \in R)\),则\((\overrightarrow{PA}+\overrightarrow{PB})\cdot \overrightarrow{PC}\)的最小值是    .

              \((4)\)如图,圆形纸片的圆心为\(O\),半径为\(5 cm\),该纸片上的等边三角形\(ABC\)的中心为\(O\).\(D\),\(E\),\(F\)为圆\(O\)上的点,\(\triangle DBC\),\(\triangle ECA\),\(\triangle FAB\)分别是以\(BC\),\(CA\),\(AB\)为底边的等腰三角形\(.\)沿虚线剪开后,分别以\(BC\),\(CA\),\(AB\)为折痕折起\(\triangle DBC\),\(\triangle ECA\),\(\triangle FAB\),使得\(D\),\(E\),\(F\)重合,得到三棱锥\(.\)当\(\triangle ABC\)的边长变化时,所得三棱锥体积\((\)单位:\(cm\)\({\,\!}^{3}\)\()\)的最大值为_____.

            • 10.

              化简\(( \overrightarrow{AB}- \overrightarrow{CD})-( \overrightarrow{AC}- \overrightarrow{BD}) \)__________\(;\)

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