Sagot :
Bonjour,
D = (3 + 7x)²
D = 7x (7x + 3) + 3 (7x + 3)
D = 49x² + 21x + 3 (7x + 3)
D = 49x² + 21x + 21x + 9
D = 49x² + 42x + 9
Bon Courage ; )
Bonjour,
D = (3 + 7x)²
D = 7x (7x + 3) + 3 (7x + 3)
D = 49x² + 21x + 3 (7x + 3)
D = 49x² + 21x + 21x + 9
D = 49x² + 42x + 9
Bon Courage ; )