d
are u sure 1st term is 8 and not 6??
Yeah
let us split this into 2,like this 5+(3+2+4/3+8/9+......) i will find the sum of the geometric series in bracket....and then add 5.. ok with this?
are you allowed to do that?
yes,i am,because it does not change the total sum....
okay so how would you get the series for the inside
1st u realize that it is geometric sequence with common ratio 2/3??
okay i see that now
the top seems like it is moving faster
so the formula for sum of infinite series is a/(1-r) where a is 1st term and r is common ratio.... so can u find the sum now?
so it would be 14?
i dont get how you know you can separate 5 +3 how come you dont do 6+2 or something like that
lets see a=3,r=2/3 \[\frac{ a }{ 1-r }=\frac{ 3 }{ 1-\frac{ 2 }{ 3 } }=\frac{ 3*3 }{ 3-2 }=9\]
that is because, the common ratio was 2/3....so the term before 2 was 2*3/2=3 that is why i wanted 3,so i split 8 as 5+3....
alright i think i got it. thanks
so u got what it converges to??
14
right?
yes :) 9+5=14...correct
thank you. should i ask another question about series here or a different thread?
as u wish :) preferably different thread,so that everyone can help but i don't mind if u put it here
ill just ask here and if you cant ill ask everyone :)
\[\sum_{k=1}^{infiniti} ((-1)^k \ln(k) )/ \ln(k+k^2)\]
does the converge if so what type or diverge or do we not have enough info for it?
nopes,sorry...weak in summation.....ask everyone....
alrighty.
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