Figure 8
Variable separation solution (19) of Eq. (3) with \(\lambda _1=\lambda _2=\lambda _3=\lambda _4=1,k_1=b_1=k_4=b_4=1\), \(\digamma _2=\textrm{sech}^2(\xi ),\digamma _3=\textrm{sech}^2(\theta )+\textrm{sech}^6(\theta )\), \(x=t=0\), \(z=\xi +2\textrm{tanh}[\xi ]+\textrm{tanh}^2[\xi ]-10\textrm{tanh}^3[\xi ],y=\theta +2\textrm{tanh}[\theta ]+\textrm{tanh}^2[\theta ]-10\textrm{tanh}^3[\theta ]\), (a) 3D plot, (b) sectional view along z-axis, (c) sectional view along y-axis.
