Répondre :
(3 x+ 5) (x - 2) - (3 x+ 5)
(3x+5) (x-2-1)
(3x+5) (x-3)
3x²-9x+5x-15 = 3x²-4x-15
delta = b²-4ac = 196
racine(delta) = 14
racines
-----------
x1 = -1,667
x2 = 3
si x=2, A = 12-8-15 = -11
(3x+5) (x-2-1)
(3x+5) (x-3)
3x²-9x+5x-15 = 3x²-4x-15
delta = b²-4ac = 196
racine(delta) = 14
racines
-----------
x1 = -1,667
x2 = 3
si x=2, A = 12-8-15 = -11
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