(2x - 5)(x + 3) ≥0
1 система :
(2x - 5)≥0 2х≥5 х≥5/2
(x + 3) ≥0 х≥-3
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_____-3__________5/2___________________ х≥5/2
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2 система :
(2x - 5)≤ 0 2х ≤ 5 х≤ 5/2
(x + 3) ≤0 х≤ -3
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_____-3__________5/2___________________ х ≤ -3
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х∈(-∞;-3]∪ [5/2 ;+∞)
рисунок 2)