Réponses

2014-02-26T18:40:12+01:00
Bonsoir
A = (3x-1)(4x-3) - (9x² -6x +1)

9x² -6x +1 = (3x - 1)²
Factorisation
A = (3x-1)(4x-3 )- (3x-1)
A = (3x-1)(4x-3 -3x +1)
A = (3x-1)(x -2)

Développement
A = 12x² -9x -4x +3 - 9x² +6x -1
A = 3x² -7x +2

3x² -7x +2 = 0
x(3x -7 +2) = 0
x(3x -5) = 0

soit x = 0
soit 3x-5 = 0
x3 = 5
x = 5/3