Hello, I need to solve this equation, please: [tex]9 {x}^{2} - 4 - 3(3x - 2) - x(3x - 2) = 0[/tex]
Mathématiques
cyberdg32
Question
Hello, I need to solve this equation, please:
[tex]9 {x}^{2} - 4 - 3(3x - 2) - x(3x - 2) = 0[/tex]
[tex]9 {x}^{2} - 4 - 3(3x - 2) - x(3x - 2) = 0[/tex]
1 Réponse
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1. Réponse Malyne
Réponse:
S = { 1/2 ; 2/3 }
Explications étape par étape:
9x² - 4 - 3(3x - 2) - x(3x - 2) = 0
9x² - 4 - 9x + 6 - 3x² + 2x = 0
6x² - 7x + 2 = 0
delta = b² - 4ac
= -7² - 4 × 6 × 2
= 49 - 48
= 1
delta > 0 donc 2 solutions !
x1 = (-b - racine carré de delta) / 2a
= (7 - racine carré de 1 ) / 2 × 6
= 6 / 12
= 1/2
x2 = (-b + racine carré delta) / 2a
= 7 + racine carré de 1 / 2 × 6
= 8 / 12
= 2/3