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kiara23
Group Title
PLEASE HELP URGENT ! what is the 7th of the geometric sequence where a1 = 3 and a5 = 768
 2 years ago
 2 years ago
kiara23 Group Title
PLEASE HELP URGENT ! what is the 7th of the geometric sequence where a1 = 3 and a5 = 768
 2 years ago
 2 years ago

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amistre64 Group TitleBest ResponseYou've already chosen the best response.1
nothings THAT urgent :/
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
we should start by remembering the general formula for a geometric sequence
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
an = a1*r^(n1)
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
we know a1, and we know the value when n=5; from this we can grab the r value
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
can you fill those in for me?
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
give it a try, ill know if its right or not :)
 2 years ago

kiara23 Group TitleBest ResponseYou've already chosen the best response.0
the answer is going to be 3,072
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
it might be, but lets see if we can build up to that
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
lets fill in what we are given: a1 = 3 and a5 = 768 when n=5 an = a1 * r^(n1) a5 = 786 = 3 * r^(51) 786/3 = r^(4) 292 = r^(4) , 4rt the whole thing to find r 4rt(292) = r as is this is not a possible sequence to me. an even root can be negative across the reals
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
an even root canNOT .... i passed typing class, honest :)
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
check your problem and make sure you havent got an error in the post
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
i got a feeling the a1 = 3 for this to work like you want it to
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
4rt(292) = r then this is what we get for r take the general formula again, knowing this r and n=7 a7 = 3 * (4rt(292))^(6) and a calculator should popout your intended results
 2 years ago

kiara23 Group TitleBest ResponseYou've already chosen the best response.0
can it be 12,288
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
...can what be?
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
a7 is going to be a negative value
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
adjust for a mismath and i get: a7 = 3 * 256^(6/4) = 12288 , so yes
 2 years ago

kiara23 Group TitleBest ResponseYou've already chosen the best response.0
can you help me with thi one ? What is the sum of the geometric sequence 4, 28, 196 ?
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
why did you think that the answer "is going to be 3,072"?
 2 years ago

kiara23 Group TitleBest ResponseYou've already chosen the best response.0
i hd my ngatives wrng
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.1
ah, itll prolly be best to post up a new question with that sum in it; i have to go for now
 2 years ago
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