Determining the Force acting on a Particle

[kacete]

Homework Statement

A particle of mass

moves across the XOY plane following the equation:

Homework Equations

The Attempt at a Solution

I'm totally clueless about this one.
I know I have to find the derivative of the movement equation to find the velocity and then again to find the acceleration and use it on Newton's Second Law of motion.
(The previous exercise was the reverse problem, given the F(t) eq, find the x(t) eq.)
I tried t=0 and t=1, and given the resulting vectors the velocity could be found?

 

[kacete]

Anyone?