ELENA00
Answered

Aider moi svp!!
Factoriser les expressions.
A = (3x - 1)2 - 81
B= (5x – 2)2 – 16
C=9- (2x - 42
D= (8x -92-1
E = (3x - 4)2-(5x - 1)2
F= 3x2-1

Sagot :

Bonjour,

a²-b² = (a+b)(a-b)

donc :

(3x-1)²-81 = (3x-1)²-9² = (3x-1+9)(3x-1-9) = (3x+8)(3x-10)

(5x-2)²-16 = (5x-2)²-4² = (5x-2+4)(5x-2-4) = (5x+2)(5x-6)

9-(2x-4)² = 3²-(2x-4)² = (3-(2x-4))(3+(2x-4)) = (3-2x+4)(3+2x-4) = (7-2x)(2x-1)

(8x-9)²-1 = (8x-9)²-1² = (8x-9-1)(8x-9+1) = (8x-10)(8x-8) = 2(4x-5)8(x-1)

                                                                                     = 16(4x-5)(x-1)

(3x-4)²-(5x-1)² = ((3x-4)-(5x-1))((3x-4)+(5x-1)) = (3x-5x-4+1)(3x+5x-4-1)

                                                                    = (-2x-3)(8x-5)

3x²-1 = (√3x)²-1² = (√3x-1)(√3x+1)

VINS

bonjour

A =  ( 3 x - 1 - 9 ) ( 3 x - 1 + 9 )

A = ( 3 x - 10 ) ( 3 x + 8 )

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

B =  ( 5 x - 6 ) ( 5 x + 2 )

C =   ( 3 + 2 x - 4 ) ( 3 - 2 x + 4 )

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

D = ( 8 x - 9 - 1 ) ( 8 x - 9 + 1 )

D = ( 8 x - 10 ) ( 8 x - 8 )

D =  16 ( 4 x - 5 ) ( x - 1 )

E = ( 3 x - 4 + 5 x - 1 ) ( 3 x - 4 - 5 x + 1 )

E = ( 8 x - 5 ) ( - 2 x - 3 )

F  = ( √3 x - 1 ) ( √3 x + 1 )