Determine whether the sequence converges or diverges. If it converges, give the limit. 60, -10, five divided by three, negative five divided by eighteen, ...
You need to find the common ratio first - divide any term by the term right before it (use the first two terms since it's easiest to)
i got -1/6
so the common ratio, r = -1/6. If |r| < 1, the sequence converges. Is |-1/6| < 1?
The fraction looks like it will eventually be a small over large, so 0. That implies it should converge. The rest is finding the limit. Have you tried this reference for the topic? http://tutorial.math.lamar.edu/Classes/CalcII/ConvergenceOfSeries.aspx
wait what
so the common ratio, r = -1/6. If |r| < 1, the sequence converges. Is |-1/6| < 1?
1/6
Yes, but is |-1/6| < 1 ?
no
Why not? 1/6 = 0.16 recurring.
oh pellet yes because its aqbsolute value
Not because it's absolute value, but because 1/6th is less than 1.
So it converges, since |r| < 1
"If it converges, give the limit. " I guess they just want what the terms approach... I don't know if they want the value of the sum or not.
Diverges Converges; 11100 Converges; 72 Converges; 0
The value of the sum: \[\Large \frac{ a_1 }{ 1-r }\]first term a1 and r, plug them in
how do i get r though
You just found r :P
In the second post you gave it
i got all -10
First term was 60, r=-1/6\[\Large \frac{ 60 }{ 1-\left( - \frac{ 1 }{ 6 }\right)}\]
60.1666
Use a calculator, and make sure you use brackets.
http://www.wolframalpha.com/input/?i=+%5Cfrac%7B+60+%7D%7B+1-%5Cleft%28+-++%5Cfrac%7B+1+%7D%7B+6+%7D%5Cright%29%7D Looks like none of the answer choices are correct for the sum, so maybe they just meant the limit of the terms The terms will approach zero, so Converges; 0
Oh man this was confusing lolol
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