Question

设集合A={x||4x-1|≥9,x∈R},B={x|≥0,x∈R},则A∩B等于(    )

A.(-3,2)

B.(-3,2)∪［0,］

C.(-∞,-3］∪［,+∞)

D.(-∞,-3)∪［,+∞)

Answer 1

答案：D

解析：∵|4x-1|≥9,∴4x-1≤-9或4x-1≥9,即A={x|x≤-2或x≥}.

又∵≥0,∴解得x＜-3或x≥0,即B={x|x＜-3或x≥0}.

∴A∩B={x|x＜-3或x≥}.