## bahrom7893 3 years ago Find the sum of the series. For what variables of x will this series converge?

1. bahrom7893

3+x+x^2+x^3+.... idk what to do about that 3

2. mathg8

3x^0 ?

3. bahrom7893

well but the next one should have been 3x and then 3x^2, etc

4. mathg8

i see ...

5. bahrom7893

@TuringTest any ideas?

6. bahrom7893

hmmm let me read through the book once more..

7. mathg8

8. bahrom7893

what's that?

9. mathg8

doesn't converge

10. mathg8

By the limit test, the series does not converge.

11. bahrom7893

It should though, for some values of x

12. bahrom7893

#22.

13. Ishaan94

x<1 ?

14. bahrom7893

im thinking partial sums or smth..

15. mathg8

I need a refresh ... rusty

16. bahrom7893

well yea but i gotta find an equation for Sum. and i can't figure out what a is

17. mathg8
18. bahrom7893

or the other side could be like ((1/3)x)

19. Ishaan94

$3 + \frac{x}{1-x}$ It only works if x<1

20. bahrom7893

math, wolf can't compute this in terms of x. ohhhhhhhhhhhhhh Ishaain u're right.

21. Ishaan94

And I am sure the series will converge only when x<1

22. bahrom7893

*Ishaan

23. bahrom7893

actually im not sure now

24. mathg8

you should try partial sums ...

25. bahrom7893

that 3 is still bothering me.

26. mathg8

what if you divide by 3?

27. bahrom7893

then a get's screwed 1+(1/3)x+(1/3)x^2, etc..

28. bahrom7893

*gets

29. bahrom7893

@radar can u take a look?

30. bahrom7893

hmm what if i start with x

31. bahrom7893

duhh that's ishaan's answer, he was right. Thanks guys!