Bonjour
Développer :
3(x+5)+(2x-1) (3+x)
= 3x + 15 + 6x + 2x² - 3 - x
= 2x² + 3x + 6x - x + 15 - 3
= 2x² + 8x + 12
(x+5)²- 3(7x+7)
= x² + 10x + 25 - 21x - 21
= x² + 10x - 21x + 25 - 21
= x² - 11x + 4
-5(2x+1)-(7-x)²
= - 10x - 5 - (49 - 14x + x²)
= - 10x - 5 - 49 + 14x - x²
= - x² - 10x + 14x - 5 - 49
= - x² + 4x - 54
(x-1) (x+1)- (x+4) (2+5x)
= x² - 1 - (2x + 5x² + 8 + 20x)
= x² - 1 - 2x - 5x² - 8 - 20x
= x² - 5x² - 2x - 20x - 1 - 8
= - 4x² - 22x - 9
