[tex]\Large\boxed{\begin{array}{l}\underline{\rm Observe~a~figura~que~anexei.}\\\sf A=~~]-2,3]~~=\{x\in\mathbb{R}/-2<x\leqslant3\}\\\sf B=~~]0,4]~~=\{x\in\mathbb{R}/0<x\leqslant4\}\\\\\tt a)~\sf A\cup B=\{x\in\mathbb{R}/-2<x\leqslant4\}\\\tt b)~\sf A\cap B=\{x\in\mathbb{R}/0<x\leqslant3\}\\\tt c)~\sf A-B=\{x\in\mathbb{R}/-2<x<0\}\\\tt d)~\sf B-A=\{x\in\mathbb{R}/3\leqslant x\leqslant4\}\end{array}}[/tex]
