hmm actually is it
An ant crawls along the radius from the center to the edge of a circular disk of radius 100 cm, moving at a constant rate of 1cm/sec. Meanwhile the disk is turning counterclockwise about its center at 1 revolution per second. Parametrize the motion of the ant.
I know it will be something like
x= _____cos (t)
but I don't know how do you find what do you put there..