The standing wave in the figure has 4 nodes and 3 antinodes.
The wavelength of a standing wave is given by,
[tex]\lambda=\frac{2}{n}L[/tex]
Where n=number of nodes-1
From the figure n=3
Therefore the wavelength is,
[tex]\lambda=\frac{2}{3}L[/tex]
Therefore the wavelength of the stationary wave produced in the given string of length L is (2/3)L.
