Bonjour
A=9-2(3x-1)
=9-6x+2
= -6x+11
B=3(4x-5)-(x+7)
=12x-15-x-7
=11x-22
C=5/2(x-6)+3/4(2x-1/6)
=5/2x-15+3/2x -1/8
=4x -121/8
D=9/10(1-9/10)x9/10x9^3/1000
=9/100x9/10x9^3/1000
=(243/1000)^2
E=(5+6x)(x-2)
=5x-10+6x^2-12x
=6x^2-7x-10
F=(-5x+3)(3x+1)
=-15x^2-5x+9x+3
=-15x^2+4x+3
Et de rien
