AsymptoticSolve

AsymptoticSolve[eqn,y->b,x->a] computes asymptotic approximations of solutions y[x] of the equation eqn passing through {a,b}.

AsymptoticSolve[eqn,{y},x->a] computes asymptotic approximations of solutions y[x] of the equation eqn for x near a.

AsymptoticSolve[eqns,{y1,y2,…}->{b1,b2,…},{x1,x2,…}->{a1,a2,…}] computes asymptotic approximations of solutions {y1[x1,x2,…],y2[x1,x2,…],…} of the system of equations eqns.

AsymptoticSolve[eqns,…,{{x1,x2,…},{a1,a2,…},n}] computes the asymptotic approximation to order n. 

AsymptoticSolve[…,Reals] computes only solutions that are real valued for real argument values.

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