Réponses

2013-06-18T13:01:31+02:00
Premier exercice :
1)a= v/t = 4+2 / 2+1 = 2 m/s2
2)V=2t-2 X=t2-2t-1
3) V2=at+Vo = 2X4-2= 6m/s
X= 1/2 at2 +Xo+Vot=16-1-8=7m
4) X= Vt+Xo X=2t-1
5) 2t-1=t2-2t-1
4t-t2=0
t=0 et 4-t=0
t=4