Respostas

2013-12-11T19:11:09-02:00
A) 0 = -30 +5t + 5t²
5t² + 5t -30 = 0
bhaskara ---->  x´= 2
                      x''= -3
C.E.:
t>0
2>0 (v)
-3>0 (f)
             -----------> S= {2}

b) S = S0 + V.T
30 = 2/v
v = 15 m/s

            ------------>  S = -30 +15t
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