bonjour
H = ( 8 x - 3 ) ( x- 4 ) - ( 2 x + 1 ) ( x - 4 )
H = 8 x² - 32 x - 3 x + 12 - ( 2 x² - 8 x + x - 4 )
= 8 x² - 35 x + 12 - 2 x² + 8 x - x + 4
= 6 x² - 28 x + 16
H = ( x - 4 ) ( 8 x - 3 - 2 x - 1 )
H = ( x - 4 ) ( 6 x - 4 )
H = 0 pour x = 4 et 2/3
donc H (2/3) = 0