Proving Convergence of the Taylor Series for 1/(1-x) as n Approaches Infinity

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In summary, to prove that Rn(x) is zero as n approaches infinity for the nth taylor polynomial of 1/(1-x) when x is between -1<x<1, you need to evaluate the nth derivative of 1/(1-x) at x=0 and simplify the resulting expression. This will show that Rn(x) approaches zero as n approaches infinity.
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Homework Statement



How do I prove that Rn(x) is zero as n approaches infinity for the nth taylor polynomial of 1/(1-x)
when x is between -1<x<1

Homework Equations




1/(1-x)
Rn(x)=M*(x-a)^(n+1)/(n+1)!
nth derivative of 1/(1-x) is n!/(1-x)^n+1

The Attempt at a Solution



the nth derivative of 1/(1-x) is n!/(1-x)^(n+1) so the max of the n+1 derivative between 0 and d if abs(d)<1 is (n+1)!(d)^(n+1)/(n+1)!(1-d)^(n+2). I simplify it and get d^(n+1)/(1-d)^(n+2) But there seems to be values of d between -1 and 1 such that when n approaches infinity, Rn approaches infinity
 
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You have to evaluate your derivatives at x=0 to get the individual terms of the taylor expansion.
 

FAQ: Proving Convergence of the Taylor Series for 1/(1-x) as n Approaches Infinity

What is Rn(x)?

Rn(x) is a function in mathematics that represents the remainder when the polynomial f(x) is divided by (x-a)n, where a is a constant and n is a positive integer.

How do you prove that Rn(x) is zero?

To prove that Rn(x) is zero, you need to show that the remainder when f(x) is divided by (x-a)n is equal to zero. This can be done by using the Remainder Theorem or by using long division.

What is the significance of proving Rn(x) is zero?

Proving that Rn(x) is zero is significant in determining the roots or solutions of the polynomial f(x). If Rn(x) is zero, it means that (x-a) is a factor of f(x) and therefore, a is a root of the polynomial.

Are there any special cases where Rn(x) is not zero?

Yes, there are special cases where Rn(x) is not zero. One example is when f(x) is a constant or a linear function. In these cases, Rn(x) will be equal to f(x) and not necessarily equal to zero.

Can Rn(x) be negative or a complex number?

Rn(x) is a remainder and therefore, it cannot be negative or a complex number. It will always be a non-negative integer or zero.

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