Bonjour !

Exercice 1 :

A= 5*3x

= 15x

B= 5+2x

C= -3x(-2x)

= 6x²

D= 9x-x

= 8x

J'ai fait le premier exercice si tu bloques pour la suite n'hésite pas à me demander !

Verified answer

Réponse :

Bonjour !

Explications étape par étape :

Exercice 1

A = 5 × 3x

A = 15x

B = 5 + 2x

→ On ne peut pas réduire

C = - 3x (- 2x)

C = 6x²

D = 9x - x

D = 8x

Exercice 2

A = 7x² - 9x²

A = - 2x²

B = 6x - 10x + 4x

B = 10x - 10x

B = 0

C = - 3 × 5x² + 7 × 2x²

C = - 15x² + 14x²

C = - x²

D = 4 × 2x + 5 × 3x - 2 × 4x

D = 8x + 15x - 8x

D = 15x

Exercice 3

A = 8x + 7 - 12x - 9

A = - 4x - 2

B = - 5x² + 8x - 3x² - 5x

B = - 8x² + 3x

C = 8 + 2x² - 6 + 4x²

C = 6x² + 2

D = - 16x + 4x - 6x - x

D = - 19x

Exercice 4

A = - 8x + 4x - 7x + 5x

A = - 6x

B = - 7x² - 3x² + 8x²

B = - 2x²

C = - 3 × 6x + 2 × 3x

C = - 18x + 6x

C = - 12x

D = 6 × 3x - 5 × 2x - 3 × 7x

D = 18x - 10x - 21x

D = - 13x

Exercice 5

A = - 6x² × 4

A = - 24x²

B = - 8x + x

B = - 7x

C = - 5x (- 8x)

C = 40x²

D = 12 - 2x

→ On ne peut pas réduire

Exercice 6

A = 4 (3x + 2) + 5x

A = 12x + 8 + 5x

A = 17x + 8

B = - 2 (5 + 4x) - 2 (4x - 5)

B = - 10 - 8x - 8x + 10

B = - 16x

C = 5 (2x² + 7) - 4x (2x + 3)
C = 10x² + 35 - 8x² - 12x

C = 2x² - 12x + 35

Exercice 7

A = (6x + 4) (3x + 7)

A = 18x² + 42 + 12x + 28
A = 18x² + 12x + 70

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

B = 12 + 9x - 8x - 6x²

B = - 6x² + x + 12

C = (5x - 2) (- 4x - 6)

C = - 20x² - 30x + 8x + 12

C = - 20x² - 22x + 12

Exercice 8

A = (- 3x + 2) (6x - 7)

A = - 18x² + 21x + 12x - 14
A = - 18x² + 33x - 14

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

B = - 6x + 8 + 12x² - 16x

B = 12x² - 22x + 8

C = (4x + 6) (2x + 3) + (3x + 2) (2x + 4)

C = 8x² + 12x + 12x + 18 + 6x² + 12x + 4x + 8

C = 14x² + 40x + 26

Exercice 9

A = - 2 + 4 × (3 - 5x)

A = - 2 + 12 - 20x

A = - 20x + 10

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

B = - 6 + 10x + 12x - 20x²

B = - 20x² + 22x - 6

C = (6x - 2)²

C = 36x² - 24x + 4

Exercice 10

A = (4x + 6) (3x + 2) - 2x²

A = 12x² + 8x + 18x + 12 - 2x²

A = 10x² + 26x + 12

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

B = 9x² + 12x - 12x - 16
B = 9x² - 16

C = (4x - 3) (2x - 4) + (2x + 7) (3x + 2)

C = 8x² - 16x - 6x + 12 + 6x² + 4x + 21x + 14

C = 14x² + 3x + 26

Exercice 11

A = (5 - 4x)²

A = 25 - 40x + 16x²

B = (4x - 2) (- 8x + 3)

B = - 32x² + 12x + 16x - 6

B = - 32x² + 28x - 6

C = (2 + 4x) (3 - 6x) - (4 + 2x) (2 - 5x)

C = 6 - 12x + 12x - 24x² - (8 - 20x + 4x - 10x²)

C = - 24x² + 6 - 8 + 20x - 4x + 10x²

C = - 14x² + 16x - 2

Exercice 12
A = 6 (2x + 7) - (5x - 3)

A  = 12x + 42 - 5x + 3

A = 7x + 45

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

B = 6x - 9 - 4x² + 6x

B = - 4x² + 12x - 9

C = 7x (2x - 4) + 3x (- 5x + 6)

C = 14x² - 28x - 15x² + 18

C = - x² - 28x + 18

Voilà ;)