Im working on putting sequences in formulas. I have the sequence:
X-X^3+X^5-X^7+X^9+....
I see the difference in exponets is Plus 2, but how do I get the negative and positive terms?
Thanks 4 Any help!!
Hello, nikie1o2!
I'm working on putting sequences in formulas. . not sure what this means
I have the sequence: .$\displaystyle x-x^3+x^5-x^7+x^9+\hdots$
I see the difference in exponents is Plus 2,
but how do I get the negative and positive terms?
If you are working with Geometric Series, then you want to identify
. . the first term $\displaystyle a$, and the common ratio, $\displaystyle r.$
In this problem, the first term is $\displaystyle x$, the common ratio is $\displaystyle \text{-}x^2$
If you are trying to write the general term for the series, $\displaystyle a_n$,
. . it looks like this: .$\displaystyle a_n \:=\:(\text{-}1)^{n+1}x^{2n-1}$