Chapter 16, Problem 55P

GO The following two waves are sent in opposite directions on a horizontal string so as to creating a standing wave in a vertical plane:

y₁(x, t) = (6.00 mm) sin(4.00πx − 400πt)

y₂(x, t) = (6.00 mm) sin(4.00πx + 400πt),

with x in meters and t in seconds. An antinode is located at point A. In the time interval that point takes to move from maximum upward displacement to minimum downward displacement, how far does each wave move along the siring?