Réponse :
Bonjour,
[tex]7 \times (-y) \times (-6) \times 9y -(-9y^2)\\\\= -7y \times (-6) \times 9y -(-9y^2)\\\\= 42y \times 9y + 9y^2\\\\= 378y^2 + 9y^2\\\\= 387y^2[/tex]
Vérification:
[tex]Pour \ x = 2\\\\7 \times (-2) \times (-6) \times 9 \times 2 -(-9 \times 2^2) = 1548\\\\387 \times 2^2 = 1548[/tex]
