Sagot :
Réponse :
a.
(x-5) (x+3)
tableau de signe de (x-5) (x+3)
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x -∞ -3 5 +∞
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(x-5) - - 0 +
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(x+3) - 0 + +
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(x-5)(x+3) + 0 - 0 +
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b.
(1-3x)(x+1)
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x -∞ - 1 1/3 +∞
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(1-3x) + + 0 -
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(x+1) - 0 + +
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(1-3x)(x+1) - 0 + 0 -
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c.
(2x+4)(x-5)(x+3)
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x -∞ -3 -2 5 +∞
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(x-5) - - - 0 +
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(x+3) - 0 + + +
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(2x+4) - - 0 + +
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(2x+4)(x-5)(x+3) - 0 + 0 - 0 +
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d.
(6-3x) / (x+4) x≠-4
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x -∞ -4 2 +∞
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(6-3x) + + 0 -
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(x+4) - 0 + +
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(6-3x) / (x+4) - ║ + 0 -
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j'espère avoir aidé
