Cho hai tập hợp \(A = \left[ { - 4;3} \right),B = \left( { - 2; + \infty } \right).A\backslash B\) bằng:
A. \(\left[ { - 4; - 2} \right)\) B. \(\left\{ { - 4; - 3; - 2} \right\}\) C. \(\left[ {3; + \infty } \right)\) D. \(\left[ { - 4; - 2} \right]\)
\(A\backslash B = \{ x \in A|x \notin B\} \)
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Ta có
\(A = \left[ { - 4;3} \right) = \left\{ {x \in \mathbb{R}\left| { - 4 \le x < 3} \right.} \right\};B = \left( { - 2; + \infty } \right) = \left\{ {x \in \mathbb{R}\left| {x > - 2} \right.} \right\}\)
Khi đó \(A\backslash B = \left\{ {x \in \mathbb{R}\left| { - 4 \le x < 3} \right.} \right\}\backslash \left\{ {x \in \mathbb{R}\left| {x > - 2} \right.} \right\} = \left\{ {x \in \mathbb{R}\left| { - 4 \le x < - 2} \right.} \right\} = [ - 4; - 2]\)
Chọn D