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            • 1.
              若函数\(f(x)= \begin{cases} \overset{x,x < 1}{x^{2}-2x-5,x\geqslant 1}\end{cases}\),则不等式\(f(x)\geqslant -2\)的解集为 ______ \(⋅\)
            • 2. 若不等式\(kx^{2}+kx- \dfrac {3}{4} < 0\)对一切实数\(x\)都成立,则\(k\)的取值范围是 ______ .
            • 3.

              设集合\(P=\{x|x^{2}-4x+3\leqslant 0\}\),\(Q=\{x|x^{2}-4 < 0\}\),则\(P\bigcup ({{\complement }_{R}}Q)=\)


              A.\([2,3]\)
              B.\((1,3)\)
              C.\((2,3]\)
              D.\((-∞,-2]∪[1,+∞)\)
            • 4.

              函数\(f(x)=-{{x}^{3}}-2{{x}^{2}}+4x\),当\(x\in [-3,3]\)时,\(f(x)\geqslant {{m}^{2}}-14m\)恒成立,则实数\(m\)的取值范围是(    )

              A.\((-3,11)\)
              B.\((3,11)\)
              C.\([3,11]\)
              D.\([2.7]\)
            • 5.

              函数\(f\left(x\right)={x}^{2}-x-2,x∈\left[-5,5\right] \),在定义域内任取一点\({{x}_{0}}\),使\(f({{x}_{0}})\leqslant 0\)的概率是

              A.\(\dfrac{1}{10}\)
              B.\(\dfrac{2}{3}\)
              C.\(\dfrac{3}{10}\)
              D.\(\dfrac{4}{5}\)
            • 6.

              已知集合\(A=\{x|x(x-1) < 0\}\),\(B=\{x|e^{x} > 1\}\),则\((C_{R}A)∩B=\)(    )

              A.\([1,+∞)\)
              B.\((0,+∞)\)
              C.\((0,1)\)
              D.\([0,1]\)
            • 7.

              若函数\(f\)\((\)\(x\)\()=\)\(x\)\({\,\!}^{3}+\)\(bx\)\({\,\!}^{2}+\)\(cx\)\(+\)\(d\)的单调递减区间为\((-1,2)\),则\(bc\)的值为(    )

              A.\(3\)         
              B.\(6\)          
              C.\(9\)           
              D.\(-6\)
            • 8.

              若函数\(f(x)=\sqrt{m{{x}^{2}}+mx+1}\)的定义域为\(R\),求实数\(m\)的取值范围.

            • 9.

              已知对于任意的\(x\in \left( -\infty ,1 \right)\cup \left( 5,+\infty \right)\),都有\({{x}^{2}}-2\left( a-2 \right)x+a > 0\),则实数\(a\)的取值范围是              

            • 10.

              不等式\(ax^{2}{+}bx{+}2{ > }0\)的解集为\(\{\left. \ x \right|{-}1{ < }x{ < }2\}\),则不等式\(2x^{2}{+}bx{+}a{ > }0\)的解集为(    )

              A.\(\{ x{ < -}1\)或\(x{ > }\dfrac{1}{2}\}\)
              B.\(\{\left. \ x \right|{-}1{ < }x{ < }\dfrac{1}{2}\}\)
              C.\(\{\left. \ x \right|{-}2{ < }x{ < }1\}\)
              D.\(\{ x{ < -}2\)或\(x{ > }1\}\)
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