Sagot :

Bonjour,

4)

x² +x -2x -2 = x² -x -2

5)

2(6-2x) / 6 -  3(x-1)/ 6=

(12 -4x -3x  +3)/6=  

(-7x +15)/6 = (15-7x) /6

6)

3x² -4x -6x +8 -8 +10x =

3x²

ephtamina890

(X-2)(X+1)

=(X×X)+(X×1)-(2×X)-(2×1)

=X^2+X-2X-2

=X^2-X-2

(6-2X ) /3 -( X-1) /2

=(2(6-2X))/6 -(3(X-1))/6

=(12-4X)/6 -(3X+3)/6

=(12-4X-3X+3) / 6

=(15-7X) / 6

(X-2)(3X-4)-2(4-5X)

=(X×3X)-(X×4)-(2×3X)+(2×4)-(2×4)+(2×5X)

=3X^2-4X-6X+8-8+10X

=3X^2-10X+8-8+10X

=3X^2