Explications étape par étape
J = ( 2x - 9 )( 8x - 4 ) = 16x² - 8x - 72x + 36 = 16x² - 80x + 36
H = ( 5x - 7 )( 3x + 2 ) = 15x² + 10x - 21x - 14 = 15x² - 11x - 14
I = ( 4x - 5 )( 5x - 1 ) = 20x² - 4x - 25x + 5 = 20x² - 29x + 5
K = ( 5 - 4x )( 2 - 2x ) = 10 - 10x - 8x + 8x² = 8x² - 18x + 10
