- #1
kidsasd987
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my professor told me any n times differentiable function can be approximated by macularine/taylor expansion.is that true? As far as I know, if the function is approximated at point a, the approximation is valid if we pick a point near a.
however, if we assume that we picked a point of a+infinite=b, how do we know the approximation can we conclude the approximation is valid or not?
For example, if we approximate a function with macularine series, and picked the point b=infinite for x, shouldn't we check the ratio test first?
ex.lima,n→∞ [ƒ(n+1)(a)*(x-a)(n+1)/(n+1)!]/[ƒ(n)(a)*(x-a)(n)/(n)!]
simplyfying this equation gives
lima,n→∞[ƒn+1(a)*(xn+1+ ... +an+1)]/[ƒn(a)*(n+1)*(xn...+an]
if it converges for every continuous smooth n time differetiable function, can anyone provie me proof?[/SUB]
however, if we assume that we picked a point of a+infinite=b, how do we know the approximation can we conclude the approximation is valid or not?
For example, if we approximate a function with macularine series, and picked the point b=infinite for x, shouldn't we check the ratio test first?
ex.lima,n→∞ [ƒ(n+1)(a)*(x-a)(n+1)/(n+1)!]/[ƒ(n)(a)*(x-a)(n)/(n)!]
simplyfying this equation gives
lima,n→∞[ƒn+1(a)*(xn+1+ ... +an+1)]/[ƒn(a)*(n+1)*(xn...+an]
if it converges for every continuous smooth n time differetiable function, can anyone provie me proof?[/SUB]
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