bonsoir
H = ( 2 x - 3 ) ( 4 x - 1 ) + ( 2 x - 3 )²
H = 8 x² - 2 x - 12 x + 3 + 4 x² - 12 x + 9
H = 12 x² - 26 x + 12
H = ( 2 x - 3 ) ( 4 x - 1 + 2 x - 3 )
H = ( 2 x - 3 ) ( 6 x - 4 )
si x = 0 , H = - 3 * - 4 = 12
si x = 3/2 , H = 0 puisque 2 x - 3 s'annule en 3/2