bonsoir Factoriser les expressions A = (x + 3)(x + 2) + (x + 3)(x + 1) B = (x + 5)(2x + 1) + (x + 5)(x – 7) C = (2x – 1)² – (3 – x)(2x – 1

Bonjour,

A = (x + 3)(x + 2) + (x + 3)(x + 1)

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

(x+3) (2x+3)

B = (x + 5)(2x + 1) + (x + 5)(x – 7)

(x+5 )( 2x+1 +x -7)=

(x+5) ( 3x -6)

C = (2x – 1)² – (3 – x)(2x – 1)

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

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

Salut !

avec un petit "svp" ça aurait été parfait !

A = (x+3)(x+2)+(x+3)(x+1)

   = (x+3)[(x+2)+(x+1)]

   = (x+3)(2x+3)

B = (x+5)(2x+1)+(x+5)(x-7)

   = (x+5)[(2x+1)+(x-7)]

   = (x+5)(3x-6)

   = 3(x+5)(x-2)

C = (2x-1)²-(3-x)(2x-1)

   = (2x-1)(2x-1)-(3-x)(2x-1)

   = (2x-1)[(2x-1)-(3-x)]

   = (2x-1)(2x+x-1-3)

   = (2x-1)(3x-4)