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            • 1.

              设集合\(A=\{x|(x-a)^{2} < 1\}\),且\(2∈A\),\(3∉A\),则实数\(a\)的取值范围为________.

            • 2.

              已知集合\(A=\left\{ (x,y)\left| {{x}^{2}}+{{y}^{2}}\leqslant 3 \right.,x\in Z,y\in Z \right\}.\)则\(A\)中元素的个数为________个.

            • 3.

              设集合\(A=\{(x,y)|y=x\}\)与集合\(B=\{(x,y)|x=a+\sqrt{1-{{y}^{2}}},a\in R\}\),若\(A\cap B\)的元素只有一个,则实数\(a\)的取值范围是\((\)     \()\)

              A.\(a=\pm \sqrt{2}\)
              B.\(-1 < a < 1\)或\(a=\pm \sqrt{2}\)
              C.\(a=\sqrt{2}\)或\(-1\leqslant a < 1\)
              D.\(-1 < a\leqslant 1\)或\(a=-\sqrt{2}\)
            • 4.

              已知集合\(A=\{x∈R|ax^{2}-3x+2=0\}\).

              \((1)\)若\(A=\varnothing \),求实数\(a\)的取值范围;

              \((2)\)若\(A\)是单元素集,求\(a\)的值及集合\(A\).

            • 5. 已知集合\(A=\{ \)\(a-\)\(2\),\(2a\),  \(5a\),\(12\}\),\(-3∈A\),则\(a\)的值为\((\)     \()\)
              A.\(-1\)     
              B.\(- \dfrac{3}{2} \)
              C.\(-1或- \dfrac{3}{2} \)
              D.\(1或- \dfrac{3}{2} \)
            • 6.

              \((1)\)已知\(y\)\(=\)\(f\)\((\)\(x\)\()\)是一次函数,且有\(f\)\([\)\(f\)\((\)\(x\)\()]=16\)\(x\)\(-15\), 则\(f\)\((\)\(x\)\()\)的解析式为 _____________________.

              \((2)\)若函数\(f\left( x \right)=\dfrac{\left( x+1 \right)\left( x+a \right)}{x}\)是奇函数,则实数\(a=\) __________.

              \((3)\)已知函数\(f\left( x \right)=x+\sqrt{2x-1}\),则\(f\left( x \right)\)的最小值为 ___________.

              \((4)\)若集合\(A=\left\{ x|a{{x}^{2}}+3x+2=0 \right\}\)中至多有\(1\)个元素, 则实数\(a\)的取值范围为 ________________.

            • 7. 已知集合\(A=\{x|ax^{2}-3x+2=0\}\)至多有一个元素,则\(a\)的取值范围是____________.
            • 8. 对于集合\(A\),若满足:\(a∈A\),且\(a-1∉A\),\(a+1∉A\),则称\(a\)为集合\(A\)的“孤立元素”,则集合\(M=\{1,2,3,…,10\}\)的无“孤立元素”的含\(4\)个元素的子集个数共有\((\)  \()\)
              A.\(28\)
              B.\(36\)
              C.\(49\)
              D.\(175\)
            • 9.
              下列结论中,表述正确的是\((\)  \()\)
              A.\(\varnothing ∈N\)
              B.\(\{2\}∈N\)
              C.\( \sqrt {2}∈N\)
              D.\(\{2\}⊆N\)
            • 10. 已知集合\(A=\{(x,y)|x^{2}+y^{2}\leqslant 1\),\(x\),\(y∈Z\}\),\(B=\{(x,y)||x|\leqslant 2\),\(|y|\leqslant 2\),\(x\),\(y∈Z\}\),定义集合\(A⊕B=\{(x_{1}+x_{2},y_{1}+y_{2})|(x_{1},y_{1})∈A\),\((x_{2},y_{2})∈B\}\),则\(A⊕B\)中元素的个数为\((\)  \()\)
              A.\(77\)
              B.\(49\)
              C.\(45\)
              D.\(30\)
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