Développer puis réduire A= (x - 4 )(x + 6) B=2(x-1)+2(y+2)-2(1+z) C=xy+ yz +xz - y (x-1)-z(y-1)-x(z-1) D=x-((1-y)-(z+1))

A= x*x+x*6-4*x-4*6 = x²+6x-4x-24= x²+2x-24

B= 2x-2+2y+4-2-2z = 2x+2y-2z 

C= xy+yz+xz-yx+y -zy+z-xz+x =x+y+z

D= x-(1-y-z-1)=x+y+z 

Bonjour

A= (x-4)(x+6)
A = x² + 6x - 4x - 24
A = x² + 2x - 24

B = 2(x-1) + 2(y+2) - 2(1+z)
B = 2x - 2 + 2y + 4 - 2 - 2z
B = 2x + 2y -2z

C = xy+ yz +xz - y(x-1) - z(y-1) - x(z-1)
C = xy + yz +xz - yx + y - zy + z -xz + x
C = x + y + z

D = x - ((1-y) - (z+1))
D = x - (1 - y - z - 1)
D = x + y + z

Voilà ^^