1. A={x ∈ R |2x-1|>3}
Ta có: |2x-1| >3
⇔\(\left[ \begin{array}{l}2x-1>3\\2x-1<-3\end{array} \right.\)
⇔\(\left[ \begin{array}{l}2x>4\\2x<-2\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x>2\\x<-1\end{array} \right.\)
⇒A= (-∞;-1) ∪ (2;+∞)
2. B={x ∈ R |x-2|<4}
Ta có: |x-2| < 4
⇔$\left \{ {{x-2 < 4} \atop {x-2>-4}} \right.$
⇔$\left \{ {{x<6} \atop {x>-2}} \right.$
⇒B=(-2;6)
A∪B=(-2;6)
A∩B=(-2;-1) ∪ (2;6)
A\B=(-∞;-2] ∪ [6;+∞)
B\A= [-1;2]
CrA=[-1;6]
CrB=(-∞;-2] ∪ [6;+∞)
CrA∩B= R\ (-2;-1) ∪ (2;6)
