bonjour
A = - x²
B = - 21 w ³
C = 2 x ( 2 - x ) x 7 x = 2 x ( 2 x - x² ) x 7 x = 4 x² - 2 x ³ x 7 x = 26 x ³
D = - 6 a * 3 a² - 4 a +( 5 b - 2 ) ( 7 - 3 b)
= - 18 a ³ - 4 a + 35 b - 15 b² - 14 + 6 b
= - 18 a ³ - 4 a - 15 b² + 41 b - 14
