Bonjour,

A = (3x + 1)(5x + 3) + (3x + 1)(2x + 2)

A = (3x + 1)(5x + 3 + 2x + 2)

A = (3x + 1)(7x + 5) ✅

B = (x - 3)(x + 1) + (x + 1)²

B = (x + 1)(x - 3 + x + 1)

B = (x + 1)(2x - 2) ✅

Bonne journée !