The displacement of a particle is given by x = (t - 2)2 where x is in meters and t in seconds. The distance covered by the particle in first 4 seconds

Velocity of the particle v=dxdt=2(t-2). Hence particle changes direction at t=2 as velocity changes from negative to positive at that instant.Therefore total distance covered by the particle from t=0 to t=4 =xt=2-xt=0+xt=4-xt=2=4+4=8 m