Finding the differential equation (initial value problem)

djh101
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Homework problem for nonlinear dynamics.


Let us write xλ(t) for the solution of the initial value problem
\dot{x} = f(x) & x(0) = λ

where f is continuously differentiable on the whole line and f(0) = 0.
a) Find the differential equation for \frac{∂x_{λ}}{∂λ}(t)


I'm a little confused about where to begin, so any sort of push in the right direction would be appreciated. Also, what does the λ subscript mean?
 
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hi djh101! :smile:
djh101 said:
\dot{x} = f(x) & x(0) = λ


I'm a little confused about where to begin, so any sort of push in the right direction would be appreciated. Also, what does the λ subscript mean?


xλ(t) is the solution to dx/dt = f(x) with initial condition x(0) = λ

hint: what can you say about xλ+dλ(t) - xλ(t) ? :wink:
 
xλ+dλ - xλ = x = ∂xλ?
 
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