Question

(理)设集合A={x|y=log₂(4-2x-x²)},B={x|≥1},则A∩B等于

A.{x|-1＜x＜-1}                      B.{x|-3＜x≤2}

C.{x|-1＜x＜1}                          D.{x|-1＜x＜-3或-1＜x≤2}

Answer 1

答案：(理)A  由4-2x-x²＞0,得x²+2x-4＜0,-1,即A=().

由≥1,得≤0,-1＜x≤2,即B=(-1,2］,∴A∩B=(-1,-1).