Take this question:
"We follow the tips of the hands of an old fashioned analog clock (360 degrees is 12 hours) . We take the clock and put it into an axis system. The origin (0,0) of the axis system is the rotationpoint of the hands. The positive x-as goes through "3 hour" and the positive y-as through "12 hour" We calculate the time "t" in hours, starting from 0:00 hours.
The equation for the tip of the big clockhand is: x=3sin2πt, y=3cost2πt
The equation for the tip of the small clockhand is x=2sin(1/6)πt, y=2cos(1/6)πt
On t=0 the two hands overlap eachother. Calculate the first point in time after t=0 when this occurs.
"This is true when cos(2πt)=cost(1/6πt) and sin(2πt)=sin(1/6πt) So, t = 12/11"
I simply don't know where to start...