Quelqu’un peut m’aider svp

Réponse:

G= 4x² +12x +9

G= (2x)² + 2×2x×3 +3²

G= (2x+3)²

H= 9x² +25 -30x

H= 9x² -30x +25

H= (3x)² - 2×3x×5 +5²

H= (3x -5)²

I= (x+3)² -16

I= (x+3)² -4²

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

I= (x-1)(x+7)

J= (x+1)² -(-3x+1)²

J= (x+1-(-3x+1))×(x+1+(-3x+1))

J= (x+1+3x-1)×(x+1-3x+1)

J= (x+3x)×(x-3x+1+1)

J= 4x × (-2x+2)

J= 4x × (-2(x -1)). Factoriser (-2x+2).

J= -4x ×2(x-1)

J= -4 ×2x(x-1)

J= -8x(x-1)

K= 81-(2x-7)²

K= 9² -(2x-7)²

K= (9-(2x-7)) × (9+(2x-7))

K= (9-2x+7)(9+2x-7)

K= (16-2x)(2+2x)

K= 2(8-x) × 2(1+x)

K= 2×2×(8-x)(1+x)

K= 4×(8-x)(1+x)

Exercice 4:

1) (3x-6)(5x-7)=0

3x-6 =0

3x = 6

3x/3 = 6/3

x = 2

5x-7 =0

5x = 7

5x/5 = 7/5

x = 7/5

L'équation a deux solutions : 2 ou 7/5

2) 3x(-2x-7) = 0

3x = 0

3x/3 = 0/3

x = 0

-2x-7 =0

-2x = 7

-2x/-2 = 7/-2

x = -7/2

L'équation a deux solutions : 0 ou -7/2

3) (7x-3)(2x+3) = 0

7x-3 = 0

7x = 3

7x/7 = 3/7

x = 3/7

2x+3 = 0

2x = -3

2x/2 = -3/2

x = -3/2