bonjours pouvez vous m'aider s'il vous plait sur les exercices 1 et 2 merci d'avance.

Bonjour,

1) Résoudre les équations :

- 2 (4 - x) + 1 = 3

- 8 + 2x + 1 = 3

2x = 3 + 8 - 1

2x = 10

x = 10/2

x = 5

3 (x - 2) - 1 = - 2 (x + 4)

3x - 6 - 1 = - 2x - 8

3x + 2x = - 8 + 6 + 1

5x = - 1

x = - 1/5

- 3x + 4 = 2 (x + 2/5)

- 3x + 4 = 2x + 4/5

- 3x - 2x = 4/5 - 4

- 5x = 4/5 - 20/5

- 25/5x = - 16

- 25x = - 16

x = 16/25

2) Développer et réduire :

A (x) = 5 (2x - 3)

A (x) = 10x - 15

B (x) = (2x - 3) (- 3x - 4)

B (x) = - 6x² - 8x + 9x + 12

B (x) = - 6x² + x + 12

C (x) = (2x - 3) - (3x - 4)

C (x) = 2x - 3 - 3x + 4

C (x) = 2x - 3x - 3 + 4

C (x) = - x + 1

D (x) = (2x - 3) (4x + 2) + (2x - 3) (- 6x - 1)

D (x) = 8x² + 4x - 12x - 6 - 12x² - 2x + 18x + 3

D (x) = 8x² - 12x² + 4x + 18x - 12x - 2x - 6 + 3

D (x) = - 4x² + 8x - 3

Factoriser D (x) :

D (x) = (2x - 3) (4x + 2) + (2x - 3) (- 6x - 1)

D (x) = (2x - 3) (4x + 2 - 6x - 1)

D (x) = (2x - 3) (4x - 6x + 2 - 1)

D (x) = (2x - 3) (- 2x + 1)