COUCOU830
Answered

Factoriser les expressions par x-3 puis
réduire.
a. (5x + 7)(x - 3) - (x - 3)(x + 2)
b. (x - 3)(2x - 5) + 2x - 6
c. (x-3)²+x-3
d. (x + 3)(x - 3) - 5(x - 3)

Pouvez vous m’aider svp

Sagot :

ECTO220

Réponse :

Bonsoir

Explications étape par étape

a) (5x+7)(x-3) - (x-3)(x+2) = (x-3)(5x+7-x-2) = (x-3)(4x+5)

b) (x-3)(2x-5) + 2x - 6 = (x-3)(2x-5) + 2(x-3) = (x-3)(2x-5+2) = (x-3)(2x-3)

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

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

FAMILYS

Bonsoir,

a. (5x + 7)(x - 3) - (x - 3)(x + 2)

= (x - 3)[(5x + 7) - (x + 2)]

= (x - 3)(5x + 7 - x - 2)

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

b. (x - 3)(2x - 5) + 2x - 6

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

= (x - 3)[(2x - 5) + 2]

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

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

c. (x - 3)² + x - 3

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

= (x - 3)[(x - 3) + 1]

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

= (x - 3)(x - 2)

d. (x + 3)(x - 3) - 5(x - 3)

= (x - 3)[(x + 3) - 5]

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

= (x - 3)(x - 2)