Réponses

2014-10-09T14:01:35+02:00
A) E=(x-3)²-(x-1)(x-2)
E=x²-6x+9-(x²-2x-x+2)
E=x²-x²-6x+3x+9-2
E=-3x+7

b) on remplace x par 100.000
(100.000-3)²-(100.000-1)(100.000-2)=99.997²-99.999x99.998
=-3*100.000+7=-299.993

c) F=(4x+1)²-(4x+1)(7x-6)
F=(4x+1)((4x+1)-(7x-6))
F=(4x+1)(-3x+7)

d) (4x+1)(7-3x)=0
⇔4x+1=0 ou 7-3x=0
⇔x=-1/4 ou x=7/3