The equation of reflected wave for soft boundary:y(x.t)=A cos[(wt-kx)]The equation of reflected wave for rigid boundary:y(x.t)=A cos[(wt+kx)]where A=amplitude of the wavew=Angular frequency of the wavet=time periodk=2 pie/lambda (lambda is the wave length of the wave).
Reflected wave equation is = A cos (Kx + wt)