Find the 9th term of the geometric sequence ..10,40,160,...
Answers
Answered by
0
10
,
40
,
160
,
640
,
2560
,
10240
,
40960
,
163840
This is a geometric sequence since there is a common ratio between each term. In this case, multiplying the previous term in the sequence by
4
gives the next term. In other words,
a
n
=
a
1
⋅
r
n
−
1
.
Geometric Sequence:
r
=
4
This is the form of a geometric sequence.
a
n
=
a
1
r
n
−
1
Substitute in the values of
a
1
=
10
and
r
=
4
.
a
n
=
(
10
)
⋅
(
4
)
n
−
1
Remove parentheses.
a
n
=
10
⋅
4
n
−
1
Substitute in the value of
n
to find the
n
th term.
a
9
=
10
⋅
4
(
9
)
−
1
Subtract
1
from
9
.
a
9
=
10
⋅
4
8
Raise
4
to the power of
8
.
a
9
=
10
⋅
65536
Multiply
10
by
65536
.
a
9
=
655360
Similar questions