bonsoir
( 2 x - 3 )² - 1 = 0
( 2 x - 3 - 1 ) ( 2 x - 3 + 1 ) = 0
( 2 x - 4 ) ( 2 x - 2 ) = 0
donc x = 4/2 = 2 ou 2/2 = 1
| x - 4 | = 8
| x - 4 | = x - 4 si x ≥ 0 donc x ≥ 4
| x - 4 | = - ( x - 4 ) dans les autres cas
x - ∞ 4 + ∞
| x - 4 | - ( x - 4 ) 0 x - 4
- ( x - 4 ) = 8
- x + 4 = 8
- x = 8 - 4
- x = 4
x = - 4
x - 4 = 8
x = 12
25 x² - 4 + ( 5 x + 2 ) ( 4 x - 7 ) = 0
( 5 x - 2 ) ( 5 x + 2 ) + ( 5 x + 2 ) ( 4 x - 7 ) = 0
( 5 x + 2 ) ( 5 x - 2 + 4 x - 7 ) = 0
( 5 x + 2 ) ( 9 x - 9 ) = 0
donc s'annule en - 2/5 et 1
