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            • 1.
              命题:“若\(a\),\(b\),\(c\)成等比数列,则\(b^{2}=ac\)”及其逆命题、否命题、逆否命题中正确的个数是______.
            • 2.
              下列四个命题中,其中为真命题的是\((\)  \()\)
              A.\(∀x∈R\),\(x^{2}+3 < 0\)
              B.\(∀x∈N\),\(x^{2}\geqslant 1\)
              C.\(∃x∈Z\),使\(x^{5} < 1\)
              D.\(∃x∈Q\),\(x^{2}=3\)
            • 3. 给出如下四个命题:
              \({①}\)若“\(p\)且\(q\)”为假命题,则\(p\)、\(q\)均为假命题;
              \({②}\)命题“若\(a{ > }b\),则\(2^{a}{ > }2^{b}{-}1\)”的否命题为“若\(a{\leqslant }b\),则\(2^{a}{\leqslant }2^{b}{-}1\)”;
              \({③}\)“\({∀}x{∈}R\),\(x^{2}{+}1{\geqslant }1\)”的否定是“\({∀}x{∈}R\),\(x^{2}{+}1{ < }1\)”;
              \({④}\)在\({\triangle }{ABC}\)中,“\(A{ > }B\)”是“\(\sin A{ > }\sin B\)”的充要条件.
              其中正确的命题的个数是\((\quad \quad)\)
              A.\(1\)                                
              B.\(2\)                                
              C.\(3\)                                
              D.\(4\)
            • 4.

              下列说法正确的是(    )

              A.命题“在\(\triangle ABC\)中,若\(\sin A{ < }\dfrac{1}{2}\), 则\(A{ < }\dfrac{\pi}{6}\)” 的逆否命题是真命题;

              B.已知不重合的直线\(a\)、\(b\)和平面\(\alpha{,}p{:}a{/\!/}\alpha{,}{且}b{/\!/}\alpha{,}q{:}a{/\!/}b\),那么\(p\)是\(q\)的充分条件;

              C.若\(\overset{\rightarrow}{a}{⋅}\overset{\rightarrow}{b}{ > }0\),则\(\overset{\rightarrow}{a}{和}\overset{\rightarrow}{b}\)夹角为锐角;若\(\overset{\rightarrow}{a}{⋅}\overset{\rightarrow}{b}{ < }0\),则\(\overset{\rightarrow}{a}{和}\overset{\rightarrow}{b}\)夹角为钝角;

              D.已知命题\(p:{∃}x\mathbb{{∈}R{,}}{使得}2^{x}{ < }x^{2}{成立}\),则\({¬}p{:∀}x\mathbb{{∈}R{,}}{均有}2^{x}{\geqslant }x^{2}\)成立;
            • 5. 给出下列命题:
              \({①}\)命题“若\(b^{2}{-}4ac{ < }0\),则方程\(ax^{2}{+}bx{+}c{=}0(a{\neq }0)\)无实根”的否命题;
              \({②}\)命题“定积分\(\int_{0}^{\sqrt{\pi}}\sqrt{\pi{-}x^{2}}dx{=}\dfrac{\pi^{2}}{4}\)”;
              \({③}\)命题“若\(a{ > }b{ > }0\),则\(\sqrt[3]{a}{ > }\sqrt[3]{b}{ > }0\)”的逆否命题;
              \({④}\)“若\(m{\geqslant }1\),则\(mx^{2}{-}2(m{+}1)x{+}(m{+}3){ > }0\)的解集为\(R\)”的逆命题.
              其中真命题的序号为\(({  })\)
              A.\({①②③}\)
              B.\({①②④}\)
              C.\({②④}\)
              D.\({①②③④}\)
            • 6.

              \((1)\)已知直线参数方程为\(\begin{cases} & x=t+3 \\ & y=3-t \end{cases}\),圆\(C\)的参数方程为\(\begin{cases} & x=2\cos \theta \\ & y=2\sin \theta +2 \end{cases}\),则圆心到直线的距离为____________。

              \((2)\)若\(∀x∈R\),\(f(x)={{({{a}^{2}}-1)}^{x}}\)是单调减函数,则\(a\)的取值范围是_________.

              \((3)\)已知函数\(f\left( x \right)={{e}^{x}}-\dfrac{1}{2}{{x}^{2}}-ax\left( a\in R \right)\),若函数\(f\left( x \right)\)的图像在\(x=0\)处的切线方程为\(y=2x+b\),则\(a+b=\)_________.

              \((4)\)下列\(4\)个命题:

              \(①\)“如果\(x+y=0\),则\(x\)、\(y\)互为相反数”的逆命题

              \(②\)“如果\({x}^{2}+x-6\geqslant 0 \),则\(x > 2\)”的否命题

              \(③\)在\(\triangle ABC\)中,“\(A > 30^{\circ}\)”是“\(\sin A > \dfrac{1}{2} \)”的充分不必要条件

              \(④\)“函数\(f(x)=\tan (x+φ) \)为奇函数”的充要条件是“\(φ=kπ(k∈Z) \)”

              其中真命题的序号是_________.

            • 7.

              \(a\),\(b\),\(c\)为三条不重合的直线,\(\alpha \),\(\beta \),\(\gamma \)为三个不重合平面,现给出四个命题:

              \(①\left. \begin{matrix} & a\parallel \gamma \\ & b\parallel \gamma \\ \end{matrix} \right\}\Rightarrow a\parallel b\);\(②\left. \begin{matrix} & \alpha \parallel c \\ & \beta \parallel c \\ \end{matrix} \right\}\Rightarrow \alpha \parallel \beta \);\(③\left. \begin{matrix} & \alpha \parallel \gamma \\ & \beta \parallel \gamma \\ \end{matrix} \right\}\Rightarrow \alpha \parallel \beta \);\(④\left. \begin{matrix} & \alpha \parallel c \\ & a\parallel c \\ \end{matrix} \right\}\Rightarrow \alpha \parallel a.\)其中正确的是\((\)   \()\).

              A.\(①②\)
              B.\(③④\)
              C.\(③\)
              D.\(③②\)
            • 8. 下列四个命题中,其中是真命题是(    )
              A.“若\(xy=1\),则\(\lg x+\lg y=0\)”的逆命题
              B.设\(x,y∈R \),命题“若\(x^{2}+y^{2}=0\)则\(xy=0\)”的否命题
              C.若\(p∧q \)为假命题,则\(p\)、\(q\)均为假命题
              D.“若\(b\leqslant 1 \),则方程\({x}^{2}-2bx+{b}^{2}+b=0 \)有实根”的逆否命题
            • 9.

              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.\(4\)
            • 10.

              “若\(x{=}0\)或\(x{=}1\),则\(x^{2}{-}x{=}0\)”的否命题为\(({  })\)

              A.若\(x{=}0\)或\(x{=}1\),则\(x^{2}{-}x{\neq }0\)
              B.若\(x^{2}{-}x{=}0\),则\(x{=}0\)或\(x{=}1\)
              C.若\(x{\neq }0\)或\(x{\neq }1\),则\(x^{2}{-}x{\neq }0\)
              D.若\(x{\neq }0\)且\(x{\neq }1\),则\(x^{2}{-}x{\neq }0\)
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