#can someone spot my error
quaint lark
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steel marsh
do all of them contain errors?
quaint lark
im not sure which since my prof disabled it
steel marsh
why is the first one inf?
quaint lark
and the first one is geometric
steel marsh
are telescoping series
the first one also appears to be a telescoping series
steel marsh
because |r| > 1
why INF and not MINF?
steel marsh
its not geometric?
it is geometric, but it also telescopes
steel marsh
so my first one is wrong
shall i check the others too?
steel marsh
so telescoping tops geometric?
i’m not sure what you mean
quaint lark
nvm i got another question
so i factored out a constant 1-e^10
and the constant times the series of e^10n
and e^10n is geometric with a common ratio of e^10
steel marsh
yes
quaint lark
and because its also telescopic it divs to -inf?
steel marsh
well, calculating it as a geometric series would give you (1-e^10) * infinity
and since 1-e^10 is negative, it becomes MINF
steel marsh
and because its also telescopic it divs to -inf?
treating it as a telescopic sequence notes that all terms cancel out except the initial e^10 and a -e^(10(∞+1)), which becomes MINF again
quaint lark
but how
steel marsh
i’m honestly not sure how to approach this, but the answer is probably a little smaller than 6
steel marsh
compare to 5^n/6^n
this is a geometric series
feral summit
it’s telescoping- i- i- can’t hold myself back
steel marsh
it’s telescoping- i- i- can’t hold myself back
are you alright??
feral summit
what about this
yeah use limit comparison test here
(if you are required to use integral test i suggest getting both of the terms in a nicer ln(x) form)
quaint lark
well, calculating it as a geometric series would give you (1-e^10) * infinity
oh wait shouldnt it be (1-e^10)* (e^10 / (1 -e^10 )) cause thatss the sum of the common ratio?
then cancel 1-e^10?
i get it now ty
cloes
cloese
close
steel marsh
oh wait shouldnt it be (1-e^10)* (e^10 / (1 -e^10 )) cause thatss the sum of ...
i believe the formula a/(1-r) only applies when |r|<1
quaint lark
ye so i sshould use 1-r^n+1/1-r instead
steel marsh
yes
rose caveBOT
@quaint lark
torn reef
+close