一质点沿直线ox方向做变速运动

1、t1=0s时x0=5m t2=2s时x2=5+2*2^3=21m t3=3s时x3=5+2*3^3=59m v1=(x2-x0)/t2=16/2=8m/sv2=(x3-x2)/t1=38m/s望采纳。...