Questions about integration of power series

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Discussion Overview

The discussion revolves around the integration of power series, specifically addressing the treatment of constants of integration and the differences between indefinite and definite integrals. Participants explore the implications of integrating power series and the role of boundary conditions in determining constants.

Discussion Character

  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions whether the constant of integration, C, in the antiderivative S(x) + C must always be zero, suggesting that it is arbitrary unless fixed by a boundary condition.
  • Another participant emphasizes that C is arbitrary by definition and can only be determined through specific conditions.
  • Participants discuss a theorem regarding the integration of a power series, noting that when integrating from b to x, the constant does not appear in the result, raising questions about how to keep track of constants in this context.
  • It is noted that the integration in the second case is a definite integral, contrasting it with the indefinite integral discussed earlier.

Areas of Agreement / Disagreement

Participants express differing views on the necessity and treatment of the constant of integration, with no consensus reached on whether it can be assumed to be zero or how to manage constants in definite integrals.

Contextual Notes

The discussion highlights the dependence on definitions and the context of integration (indefinite vs. definite), which may influence the treatment of constants.

hyper
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Lets say we have this series:

a0+ a1(x-k)^1 +a2(x-k)^2 +a3(x-k)^3 = s(x)

If I integrate the series a theorem in the books says that I will get the antiderivate S(x)+C, but won't C allways be equal to zero?
 
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hyper said:
Lets say we have this series:

a0+ a1(x-k)^1 +a2(x-k)^2 +a3(x-k)^3 = s(x)

If I integrate the series a theorem in the books says that I will get the antiderivate S(x)+C, but won't C allways be equal to zero?
Why should it be zero? Upon taking the derivative of S(x) + C, one obtains the original sum s(x).

C is arbitrary by definition, unless it is fixed by a boundary condition.
 
I read this in another theorem:

f(x)= (sigma from n=0 to eternity) an(x-b)^n an is like a0 a1 a2 a3 etc

then:
integrate from b to x f(t) dt= (sigma from n=0 to eternity) an/(n+1)* (x-b)^(n+1)


Here it is no constant, how can I keep track of the constants?
 
hyper said:
I read this in another theorem:

f(x)= (sigma from n=0 to eternity) an(x-b)^n an is like a0 a1 a2 a3 etc

then:
integrate from b to x f(t) dt= (sigma from n=0 to eternity) an/(n+1)* (x-b)^(n+1)


Here it is no constant, how can I keep track of the constants?
Note that in this case you are integrating between limits, i.e. you are evaluating the definite integral, whereas in the previous case you were evaluating the indefinite integral.
 

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