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            • 1.

              已知命题\(p\)\(m\)\(∈R\),且\(m\)\(+1\leqslant 0\),命题\(q\):\(∀\)\(x\)\(∈R\),\(x\)\({\,\!}^{2}+\)\(mx\)\(+1 > 0\)恒成立,若\(p\)\(∧\)\(q\)为假命题,则\(m\)的取值范围是___________.

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

              下列说法中正确的是

              \(①\)“\(\forall x > 0\),都有\(x^{2}-x+1\geqslant 0\)”的否定是“\(\exists {{x}_{0}}\leqslant 0\),\(x_{0}^{2}-x_{0}+1 < 0\)”.

              \(②\)已知\(\{a_{n})\)是等比数列,\(S_{n}\)是其前\(n\)项和,则\(S_{n}\),\(S_{2n}-S_{n}\),\(S_{3n}-S_{2n}\),也成等比数列.

              \(③\)“事件\(A\)与事件\(B\)对立”是“事件\(A\)与事件\(B\)互斥”的充分不必要条件.

              \(④\)已知变量\(x\),\(y\)的回归方程是\(\hat{y}=200-10x\),则变量\(x\),\(y\)具有负线性相关关系.

              A.\(①④\)
              B.\(②③\)
              C.\(②④\)
              D.\(③④\)
            • 4.

              命题\(p:\)若\(x < 0\),则\(\ln \left( x+1 \right) < 0\);\(q\)是\(p\)的逆命题,则\((\)   \()\)

              A.\(p\)真,\(q\)真      
              B.\(p\)真,\(q\)假   
              C.\(p\)假,\(q\)真          
              D.\(p\)假,\(q\)假
            • 5.

              命题“若\(a,b\)都是无理数,则\(a+b\)是无理数”与它的逆命题、否命题、逆否命题中,真命题的个数是\((\)   \()\)

              A.\(0\)
              B.\(2\)
              C.\(4\)
              D.不确定
            • 6.

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

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

              C.若\(x\neq 1 \)且\(x\neq -1 \),则\({x}^{2}\neq 1 \)
              D.若\(x\neq 1 \)或\(x\neq -1 \),则\({x}^{2}\neq 1 \)
            • 7. \(①\)一个命题的逆命题为真,它的否命题也一定为真;
                \(②\)在\(\triangle ABC\)中,“\(∠B=60^{\circ}\)”是“\(∠A\),\(∠B\),\(∠C\)三个角成等差数列”的充要条件.
               \(③\)已知\(a,b∈R \),则“\(ab=1 \)”是直线“\(ax+y-1=0 \)”和直线“\(x+by-1=0 \)”平行的充分不必要条件\(.④\)“ \(am\)\({\,\!}^{2} < \) \(bm\)\({\,\!}^{2}\)”是“ \(a\)\( < \) \(b\)”的充分必要条件.
              以上说法中,所有正确命题的序号的为 ______.
            • 8.

              已知函数\(3 < x\leqslant 7\),记\({{f}_{0}}(x)={f}{{'}}(x)\),\(\begin{cases} a=-1 \\ b=-1 \\\end{cases}\),\(…\),\({{f}_{n}}(x)={{{f}{{'}}}_{n-1}}(x)\)且\({{x}_{2}} > {{x}_{1}}\),对于下列命题:

              \(①\)函数\(f(x)\)存在平行于\(x < -\dfrac{1}{3}\)轴的切线;   \(②x > 1\);

              \(③{{f}^{{{'}}}}(x) < 0\); \(④-\dfrac{1}{3} < x < 1\).

              其中正确的命题序号是____________\((\)写出所有满足题目条件的序号\()\).

            • 9.

              \((1)\)若圆\(x\)\({\,\!}^{2}+\)\(y\)\({\,\!}^{2}-2\)\(x\)\(-4\)\(y\)\(=0\)的圆心到直线\(x\)\(-\)\(y\)\(+\)\(a\)\(=0\)的距离为\( \dfrac{ \sqrt{2}}{2}\),则\(a\)的值为________.

              \((2)\)已知等比数列\(\{a_{n}\}\)满足\(a_{1}=3\),且\(4a_{1}\),\(2a_{2}\),\(a_{3}\)成等差数列,则此数列的公比等于________

              \((3)\)向量\(a=(\)入\(.2)\),\(b=(-3.5)\),且\(a\)与\(b\)的夹角是锐角,则入得取值范围是________

              \((4)\)给出以下结论:

              \(①\)直线\({l}_{1},{l}_{2} \)的倾斜角分别为\({a}_{1},{a}_{2} \),若\({{l}_{1}}\bot {{l}_{2}}\),则\(|{{\alpha }_{1}}-{{\alpha }_{2}}|={{90}^{\circ }}\);

              \(②\)对任意角\(\theta \),向量\({{e}_{1}}=(\cos θ,\sin θ) \)与\({e}_{2}=\left(\cos θ- \sqrt{3}\sin θ, \sqrt{3}\cos θ+\sin θ\right) \)的夹角都为\(\dfrac{\pi }{3}\);

              \(③\)若\(\Delta ABC\)满足\(\dfrac{a}{\cos B}=\dfrac{b}{\cos A}\),则\(\Delta ABC\)一定是等腰三角形;

              \(④\)对任意的正数\(a,b \),都有\(1 < \dfrac{\sqrt{a}+\sqrt{b}}{\sqrt{a+b}}\leqslant \sqrt{2}\).

              其中所有正确结论的编号是_____________.

            • 10.

              给定如下命题:

              \(①\)若命题\(p\):\(\forall x\geqslant 0\),\(x^{2}+x\geqslant 0\)。则\(\neg p\):\(\exists {{x}_{0}} < 0\),\({{x}_{0}}^{2}+{{x}_{0}} < 0\)

              \(②\)若变量\(x\),\(y\)线性相关,其回归方程为\(\widehat{y}+x=2\),则\(x\),\(y\)正相关

              \(③\)在\(\triangle ABC\)中,\(BC=2\),\(AC=3\),\(\angle B=\dfrac{\pi }{3}\),则\(\triangle ABC\)是锐角三角形

              \(④\)将长为\(8\)的铁丝围成一个矩形框,则该矩形面积大于\(3\)的概率为\(\dfrac{1}{2}\)

              \(⑤\)已知\(a > b > c > 0\),且\(2b > a+c\),则\(\dfrac{b}{a-b} > \dfrac{c}{b-c}\)

              其中正确命题是________\((\)只填序号\()\).

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