一质点沿直线Ox方向做变速运动,它离开O点的距离x随时间变化的关系为x=8+2t²(m)

3个回答

  • 1.[(8+2*2²)-(8+2*0²)]/2=4m/s

    2..[(8+2*3²)-(8+2*2²)]/(3-2)=10m/s