## Dido525 Summation limit: one year ago one year ago

1. math>philosophy

plzzzz just type the question when you post

2. Dido525

|dw:1353736632757:dw|

3. Dido525

Well it's better when I draw it out.

4. Dido525

The answer is 8 but I have no idea why. @math>philosophy @satellite73

5. satellite73

the answer is 8? i don't think that is right

6. math>philosophy

It shouldn't be 8. Are you still doing Riemann sums?

7. Dido525

Well according to maple it's 8.

8. math>philosophy

Then there must be a syntax error

9. Dido525

I checked on wolfram too.

10. satellite73

oh i am a dope

11. Dido525

Let me double check.

12. satellite73

the index is $$i$$ but the expression is $$\frac{8}{n}$$

13. Dido525

Yeah.

14. math>philosophy

oh

15. satellite73

so it is a constant

16. Dido525

Well I know that but then we have: |dw:1353736967140:dw|

17. satellite73

$\sum_{i=1}^n\frac{8}{n}=\frac{8}{n}+\frac{8}{n}+...+\frac{8}{n}$ where there are $$n$$ terms and that gives you 8 for all $$n$$

18. Dido525

How? If I said n =1 and then n=2 they aren't the same.

19. perl

sigma of 1 is n , so

20. Dido525

Ohh right!!!! I feel like an idiot....

21. satellite73

are you summing over $$i$$ or over $$n$$ ?

22. Dido525

Got it! Thanks everyone :) .

23. satellite73

ok