Réponse :
Explications étape par étape :
A = (3+x)²
= 3² + 2X3Xx + x²
= 9 + 6x + x²
= x² + 6x + 9
B = (x + 5 )²
= x² + 2XxX5 + 5²
= x² + 10x + 25
C = (2x + 1 )²
= (2x)² + 2X(2x)X1 + 1²
= 4x² + 4x + 1
D = (-4x + 3 )²
= (-4x)² + 2X(-4x)X3 + 3²
= 16x² - 24x + 9
E = (1 + 3x)²
= 1² + 2X1X3x + (3x)²
= 1 + 6x + 9x²
= 9x² + 6x + 1
F = (x² + 1 )²
= (x²)² + 2Xx²X1 + 1²
= x^4 + 2x² + 1