anonymous one year ago Write the sum using summation notation, assuming the suggested pattern continues. -1 + 2 + 5 + 8 + ... + 44 summation of negative three times n from n equals zero to fifteen summation of the quantity negative one plus three n from n equals zero to fifteen summation of negative three times n from n equals zero to infinity summation of the quantity negative one plus three n from n equals zero to infinity @dan815 @solomonzelman @mathstudent55 @luigi0210 @sammixboo

1. Haseeb96

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2. anonymous

okay so what do we do next @ha

3. anonymous

@Haseeb96

4. misty1212

HI!!

5. misty1212

they are asking for sigma notation, not a formula for the sum, right?

6. anonymous

yes @misty1212

7. Haseeb96

okay okay @misty1212 you should help her I dont know how to solve summatation question and tell us in easy way how to find out the summation

8. misty1212

$\sum_{n=-1}^{?}-1+3n$ looks good now we need the upper limit

9. misty1212

oops that is wrong, i meant $\sum_{n=0}^{?}-1+3n$ because you are adding 3 each time

10. Haseeb96

how did you take out this expression (-1+3n) ? @misty1212

11. anonymous

i think it would be infinity on top

12. misty1212

to figure out the upper limit, set $1+3n=44$ solve for $$n$$ you should get $$n=15$$ making your answer $\huge\sum_{n=0}^{15}-1+3n$

13. misty1212

ok it does say "assuming the pattern continues" so maybe they want $\sum_{n=0]^{\infty}--+3n$

14. misty1212

dang $\sum_{n=0}^{\infty}-1+3n$

15. misty1212

which is kind of silly since that is not a number, but whatever

16. anonymous

thank you so much @misty1212