Use a power series to approximate the integral 1/(1+x^3) from (2/3) to 0 Use a power series to approximate the integral 1/(1+x^3) from (2/3) to 0 @Mathematics
like taylor series?
A series of the form \[\sum_{n = 0}^{\infty} a _{n}(x-c)^{n}\]
any idea how to start that?
Nope. I know what individually they mean. asubn is a sequence and x is a variable of sort. An integral is the area under a curve so graphically.
graphically your trying to match a polynomial to the curve of the given equation. you do that by matching derivatives ....
you gather up enough derivatives and you can fit the curve; because derivatives tell you how a curve bends and moves
\[(1+x^3)^{-1}\] \[-3x^2(1+x^3)^{-2}\] \[-6x(1+x^3)^{-2}+18x^4(1+x^3)^{-3}\] \[\begin{array}l-6(1+x^3)^{-2}&+36x^3(1+x^3)^{-3}\\ &+72x^3(1+x^3)^{-3}-162x^6(1+x^3)^{-4}\end{array}\] but that can get messy
you find values for those at a given "value" in the interval that you are looking at; perferabbly a simple enough value like 0 works since its in your interval
those become the coeffs of your power series
1 0x 0x^2 −6x^3 and so on .....
http://www.wolframalpha.com/input/?i=y+%3D+1-6x%5E3+and+y%3D1%2F%281%2Bx%5E3%29 if you get enough derivatives under your belt, you can see that the curves are starting to match in the interval
i messed up on the coeffs, but the wolf says my poly degrees was good
1-x^3+x^6-x^9+x^12-x^15
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