Lag1989 task 1.29

The velocity of a particle moving in the XY plane; varies with time according to the law V = (1-0.5t) i + 4j. At the moment t = 0, the particle coordinates x₀ = y₀ = 0. Find the extremal value of the coordinate x₁ of the particle and the coordinate y₁ corresponding to the same instant of time. Record the dependence of the radius vector r of the particle on time.