设全集U=R,集合A={x|x≤1或x≥3},集合B={x|k

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设全集U=R,集合A={x|x≤1或x≥3},集合B={x|k
设全集U=R,集合A={x|x≤1或x≥3},集合B={x|kk+1>1或1

设全集U=R,集合A={x|x≤1或x≥3},集合B={x|k
A={x|x=3}
CuA={x|1

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这题怎么设A={X│-2≤X≤a(a≥-2},B={Y│y=2x+3,x∈A},C={Z│Z=X*X,X∈A}求使C是B的子集成立的a先求B={y|-1<=y<=2a+3}
(1)若a>2,C={z|0<=z<=a^2}
(2)若0=< a <=2,c={z|0<=z<=4}
(3)若-2=< a <0,c={z|a^2<=z<=4}
要使C是B的子集,
若...

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这题怎么设A={X│-2≤X≤a(a≥-2},B={Y│y=2x+3,x∈A},C={Z│Z=X*X,X∈A}求使C是B的子集成立的a先求B={y|-1<=y<=2a+3}
(1)若a>2,C={z|0<=z<=a^2}
(2)若0=< a <=2,c={z|0<=z<=4}
(3)若-2=< a <0,c={z|a^2<=z<=4}
要使C是B的子集,
若(1)则a^2<=2a+3 则2若(2)则2a+3>=4,1/2<=a<=2
若(3)则2a+3>=4,结果为空
综合(1)(2)(3)得
a∈[1/2,3]的取值范围

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