Coordinates for the tip of the shorter hand at this time are (, ) = (4*cos(60°),4*sin(60°)) = ( , ) = ( , ). Coordinates for the tip of the longer hand at this time are ( , ) = (0,6). Now apply the formula for the distance between two points in a coordinate plane given by their coordinates = + . In your case, dx = = -2; dy = = . Therefore, = + . At this point, I leave it to you to complete calculations. You just have all needed instructions, and the way is clear.