А) (-∞; 2,5) ∩ (-4; 3]
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-----o-----------o-------*----->x
-4 2.5 3
x∈{-3, -2, -1, 0, 1, 2}
б) [-5; 2] ∪ [2; 4]
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------*-----*-------*-------->x
-5 2 4
x∈{-5; -4; -3; -2; -1; 0 ; 1; 2; 3; 4}
в) (-11; 0) ∩ (-3; 5)
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------o---------o--------o------o----->x
-11 -3 0 5
x∈{-3; -2; -1; 0}