Évaluation svpp svppp

Bonjour,

1)

k (a + b) = ka + kb

k (a - b) = ka - kb

2)

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

A = x + 3 - x - 5

A = x - x + 3 - 5

A = - 2

B = - 4x + x² + (6 + 5x²) + 3x + 2x

B = - 4x + x² + 6 + 5x² + 3x + 2x

B = x² + 5x² - 4x + 3x + 2x + 6

B = 6x² + x + 6

3)

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

C = 3x - 6 + 15 - 5x

C = 3x - 5x - 6 + 15

C = - 2x + 9

D = 2x (x + 5) + x² (1 - x)

D = 2x² + 10x + x² - x³

D = - x³ + 2x² + x² + 10x

D = - x³ + 3x² + 10x

4)

a. A = 3xy - 4y

A = y (3x - 4)

b. B = 2 (x - 3) + (x - 3) (x + 3)

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

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

c. Pour x = 3 et y = -1

A = 3xy - 4y

A = 3 * 3 * - 1 - 4 * - 1

A = 9 * - 1 - 4 * - 1

A = - 9 + 4

A = - 5.

Réponse :

Explications étape par étape

Bonjour

Exercice 1 :

k(a + b) = k * a + k * b = ak + bk

tu peux mettre une flèche qui va de k vers a et une autre qui va de k vers b

k(a - b) = k * a - k * b = ak - bk

Exercice 2 :

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

A = x + 3 - x - 5

A = -2

B = -4x + x² + (6 + 5x²) + 3x + 2x

B = -4x + x² + 6 + 5x² + 5x

B = 6x² + x + 6

Exercice 3 :

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

C = 3 * x + 3 * (-2) + 5 * 3 + 5 * (-x)

C = 3x - 6 + 15 - 5x

C = -2x + 9

D = 2x(x + 5) + x²(1 - x)

D = 2x * x + 2x * 5 + x² * 1 + x² * (-x)

D = 2x² + 10x + x² - x³

D = -x³ + 3x² + 10x

Exercice 4 :

A = 3xy - 4y

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

a) Factoriser A :

A = 3x * y - 4 * y

A = y(3x - 4)

b) factoriser B :

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

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

c) calculer A pour x = 3 et y = -1 :

A = -1(3 * 3 - 4)

A = -1(9 - 4)

A = -1 * 5

A = -5