Let
\begin{cases}
u_t(x,t) + u(x,t)u_x(x,t) = 0, & \text{for } x\in\mathbb{R},\; t > 0 \\
u(x,0) = h(x), & \text{for } x\in\mathbb{R}.
\end{cases}
Suppose that h ∈ C²(R) and that h′(x)>0 for all x ∈ R. Check, with the help of implicit function theorem, for (x , t)sufficiently close to (x0 , 0) (where x0 ∈ R is a fixed number), that the equation
u=h(x−tu)
defines a solution to the Cauchy problem (for x sufficiently close to x0 and t close to zero).
\begin{cases}
u_t(x,t) + u(x,t)u_x(x,t) = 0, & \text{for } x\in\mathbb{R},\; t > 0 \\
u(x,0) = h(x), & \text{for } x\in\mathbb{R}.
\end{cases}
Suppose that h ∈ C²(R) and that h′(x)>0 for all x ∈ R. Check, with the help of implicit function theorem, for (x , t)sufficiently close to (x0 , 0) (where x0 ∈ R is a fixed number), that the equation
u=h(x−tu)
defines a solution to the Cauchy problem (for x sufficiently close to x0 and t close to zero).