优优班--学霸训练营 > 知识点挑题
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            • 1.
              在下列命题中,不正确的是\((\)  \()\)
              A.\(\{1\}∈\{0,1,2\}\)
              B.\(\varnothing ⊆\{0,1,2\}\)
              C.\(\{0,1,2\}⊆\{0,1,2\}\)
              D.\(\{0,1,2\}=\{2,0,1\}\)
            • 2. 若对任意的\(x∈D\),均有\(f_{1}(x)\leqslant f(x)\leqslant f_{2}(x)\)成立,则称函数\(f(x)\)为函数\(f_{1}(x)\)到函数\(f_{2}(x)\)在区间\(D\)上的“折中函数”\(.\)已知函数\(f(x)=(k-1)x-1\),\(g(x)=0\),\(h(x)=(x+1)\ln x\),且\(f(x)\)是\(g(x)\)到\(h(x)\)在区间\([1,2e]\)上的“折中函数”,则实数\(k\)的值构成的集合是 ______ .
            • 3.

              集合\(A=\{1,3,a^{2}\}\),集合\(B=\{a+1,a+2\}\),若\(B∪A=A\),则实数\(a=\)_________.

            • 4.

              设集合\(A{=}\left\{ \left( {{x}_{1}},{{x}_{2}},{{x}_{3}},{{x}_{4}},{{x}_{5}} \right)\left| {{x}_{i}}\in \{-1,0,1\},i=1,2,3,4,5 \right. \right\}\),那么集合\(A\)中满足条件“\(1\leqslant \left| {{x}_{1}} \right|+\left| {{x}_{2}} \right|+\left| {{x}_{3}} \right|+\left| {{x}_{4}} \right|+\left| {{x}_{5}} \right|\leqslant 3\)”的元素个数为

              A.\(60\)                          
              B.  \(90\)                              
              C.\(120\)                           
              D.\(130\)
            • 5.

              已知集合\(A=\{-1,0,a\}\),\(B=\{0,\sqrt{a} \}.\)若\(B⊆A\),则实数\(a\)的值为______.

            • 6.

              若集合\(A{=}\{ 1{,}x,4\}\),\(B{=}\{ 1{,}x^{2}\}\),且\(B{⊆}A\),则\(x{=}(\)  \()\)

              A.\(2\),或\({-}2\),或\(0\)                                                     
              B.\(2\),或\({-}2\),或\(0\),或\(1\)
              C.\(2\)                                                                                             
              D.\({±}2\)
            • 7. 设集合\(A=\{1,2,4\}\),集合\(B=\{x|x=a+b,a∈A,b∈A\}\),则集合\(B\)中的元素个数为______.
            • 8. 已知集合\(A=\{y|y=|x|-1,x∈R\}\),\(B=\{x|x\geqslant 2\}\),则下列结论正确的是\((\)  \()\)
              A.\(-3∈A\)
              B.\(3∉B\)
              C.\(A∩B=B\)
              D.\(A∪B=B\)
            • 9. 设\(A\),\(B\)是非空集合,定义\(A×B=\{x|x∈A∪B\)且\(x∉A∩B\}\),已知\(A=\{x|y= \sqrt {2x-x^{2}}\}\),\(B=\{y|y=2^{x},x > 0\}\),则\(A×B=\)______.
            • 10.
              用\(C(A)\)表示非空集合\(A\)中元素的个数,定义\(A*B= \begin{cases} \overset{C(A)-C(B)\;,C(A)\geqslant C(B)}{C(B)-C(A)\;,C(A) < C(B)}\end{cases}\)若\(A=\{1,2\}\),\(B=\{x|(x^{2}+ax)(x^{2}+ax+2)=0\}\),且\(A*B=1\),设实数\(a\)的所有可能取值构成集合\(S\),则\(C(S)=(\)  \()\)
              A.\(4\)
              B.\(3\)
              C.\(2\)
              D.\(1\)
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