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已知集合A={x|x2-5x+6>0,x∈R},B={x||x-2a|≤2,x∈...
已知集合A={x|x2-5x+6>0,x∈R},B={x||x-2a|≤2,x∈R},若A∪B=R,则实数a的取值范围是 .
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的数;β:整数的
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,则A
B所以α是β的
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2-3x+3)•e
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