the second term of geometric sequence is 6 and the fifth term is _48. find also, in simplified form, of the first n terms of this sequence.
3 answers
what is the answer
r^(5 - 2) = 48 / 6 ... r^3 = 8 ... r = 2
An = 3 * 2^(n-1)
An = 3 * 2^(n-1)
Just use your definitions:
"the second term of geometric sequence is 6" ----> ar = 6
"the fifth term is - 48" ---> ar^4 = -48
divide them:
(ar^4)/(ar) = -48/6
solve for r, since the a's will divide out
then plug that back into ar=6
sub into the formula for the sum of n terms.
let me know what you get
"the second term of geometric sequence is 6" ----> ar = 6
"the fifth term is - 48" ---> ar^4 = -48
divide them:
(ar^4)/(ar) = -48/6
solve for r, since the a's will divide out
then plug that back into ar=6
sub into the formula for the sum of n terms.
let me know what you get