Hello I am going over the old ETS exams and I am having trouble with #6 of the 8677 exam. The question is:

A particle is initially at rest at the top of a curved frictionless track. The x&y coordinates of the track are related in dimensionless units by y=x^2/4, where the positive y-axis is in the vertical downward direction. As the particle slides down the track, what is its tangential acceleration.

Now I viewed the solutions on the site grephysics.net but I feel there is a better way to do the problem like just taking some derivatives or something but I cant figure it out. So if you solved it a different way from the people on that site when you were studying please post here and let me know. Thanks for your time!