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

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amistre64
 3 years ago
Best ResponseYou've already chosen the best response.1nothings THAT urgent :/

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

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

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

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

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

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

amistre64
 3 years ago
Best ResponseYou've already chosen the best response.1lets 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

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

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

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

amistre64
 3 years ago
Best ResponseYou've already chosen the best response.14rt(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

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

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

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

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

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