Réponse:
bonjour
1. 36x² - 25
= (6x - 5)(6x + 5)
(3eme identité remarquable)
2. 36x² - 25 - (3x+1)(6x-5)
= (6x - 5)(6x + 5) - (3x +1)(6x-5)
= (6x-5)(6x + 5 -(3x+1))
= (6x-5)(6x+5-3x-1)
= (6x-5)(3x+4)
3. (6x-5)(3x+4)
6x -5 = 0 3x +4 = 0
6x = 5 3x = -4
x = 5/6 x = -4/3