Réponses

2012-10-25T16:44:10+02:00

E = (2x²-3x+10x-15) - (5x+10)

E = 2x² +7x-15-5x-10

E = 2x²+2x-25

 

Pour x = 0, E = 0

Pour x = 5

E = 2*25+2*5-25

E = 50+10-25 = 35

2012-10-25T16:44:18+02:00

E=(x+5)(2x-3)-5(x+2)=x²-3x+10x-15-5x-10=x²+2x-15

x=0, E=0²+2*0-15=-15

x=5, E=5²+2*5-15=25+10-15=20