Bonjour, vous pouvez m'aider svp ? : Développer et réduire les expressions suivantes : A = -(2x + 5) + (-3x - 1) B = -8(2x - 7) +3(7x +1) C = 5x(x -8) - x(x - 1

Bonjour,

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

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

A = -2x - 5 - 3x - 1

A = -5x - 6

B = -8(2x - 7) +3(7x +1)

B = -8*2x - 8*(-7) + 3*7x + 3*1

B = -16x + 56 + 21x + 3

B = 5x + 59

C = 5x(x -8) - x(x - 1)

C = 5x*x + 5x*(-8) - x*x - x*(-1)

C = 5x² - 40x - x² + x

C = 4x² + 39x

D = 5x (2x - 3) - 5(x2 - 4)

D = 5x*2x + 5x*(-3) - 5*x² - 5*(-4)

D = 10x² - 15x - 5x² + 20

D = 5x² - 15x + 20

E= -34-4x + 3) - (x + 3)

E = -34 - 4x + 3 - x - 3

E = -5x - 34

F = 3(x - 1) - x(x - 4) + 2x²

F = 3*x - 3*1 - x*x - x*(-4) + 2x²

F = 3x - 3 - x² + 4x + 2x²

F = x² + 7x - 3

Si x=1

F = 1² + 7*1 - 3

F = 1 + 7 - 3

F = 5

Si x = -2

F = (-2)² + 7*(-2) - 3

f = 4 - 14 - 3

F = -10 - 3

F = -13

Si x = 4

F = 4² + 7*4 - 3

F = 16 + 28 - 3

F = 44 - 3

F = 41

Bonne journée