Question

What is the 8th term of the geometric sequence where a1 = 243 and a4 = 9?

Answer 1

Find the common ratio r first using the explicit def of geo seq\[a(n)=a _{1}r^{n-1}\]\[9=243r^{4-1}\]\[r^3=27\]\[r=3\]

Answer 2

r should equal 1/3 tho...

Answer 3

as 243*3^2=6561...

Answer 4

or your initial equation should have been a1/r^(n-1)

Answer 5

other than that, ya

Answer 6

correct r=1/3

\[a(8)=243\left( \frac{1}{3} \right)^{8-1}=\frac{1}{9}\]

Answer 7

these are the answers given to choose from
0.0123456

0.037037

0.11111

0.3333

Answer 8

1/9=0.1111111

Answer 9

thanx champ

Answer 10

What is the simplified form of