Exercice 1 :
(9 - 2x)(x+6) + 7(2x - 5)
= 9x + 54 - 2x² -12x + 14x - 35
= 2x² + 11x + 19
(2x + 5)²
=(2x + 5)(2x + 5)
=4x² + 10x + 10x + 25
= 4x² + 20x + 25
Exercice 2 :
Question 1 -
on choisit 3
3 - 1 = 2
2² = 4
4 + 6 = 10
Oui on obtient bien 10.
Question 2
on choisit 3
3² = 9
on ajoute 1 = 10
Question 3
on choisit -2
- 2 - 1 = -3
(-3)² = 9
9 - (-4) = 9 + 4 = 13
Question 4
x² + 1 = 5
x² = 4
x = 2
Question 5
Programme A = (x - 1)² + 2x
= (x-1)(x-1) + 2x
= x² -x -x + 1 + 2x
= x² + 1
Programme B = x² + 1
Oui les deux programmes sont identiques.
