the radius vector of a point A relative to the origin varies with time t as r→=at î -bt2 j^, where a and b are positive constants and i^ and j^ are the unit vectors of x and y axis . find-
1)the eqn of the point's trajectory y(x); plot this function .
2)the time dependence of the velocity v and acceleration a vectors as well as of the moduli of these quantities .
