bonjour
x
2 x - 7
( 2 x - 7 )²
( 2 x - 7 )² - 9
4
8 - 7 = 1
1² = 1
1 - 9 = - 8
r (x) = ( 2 x - 7 )² - 9
R (x) = ( 2 x - 7 - 3 ) ( 2 x - 7 + 3 )
R (x) = ( 2 x - 10 ) ( 2 x - 4 )
r (x) = 0 pour x = 10/2 = 5 et x = 4/2 = 2
antécédents de - 9
( 2 x - 7 )² - 9 = - 9
( 2 x - 7 )² = - 9 + 9 = 0
2 x - 7 = 0 pour x = 7 /2
R