AsymptoticDSolveValue

AsymptoticDSolveValue[eqn,f,x->x0] computes an asymptotic approximation to the differential equation eqn for f[x] centered at x0.

AsymptoticDSolveValue[{eqn1,eqn2,…},{f1,f2,…},x->x0] computes an asymptotic approximation to a system of differential equations.

AsymptoticDSolveValue[eqn,f,x,ϵ->ϵ0] computes an asymptotic approximation of f[x,ϵ] for the parameter ϵ centered at ϵ0.

AsymptoticDSolveValue[eqn,f,…,{ξ,ξ0,n}] computes the asymptotic approximation to order n. 

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