Use the formula below to find the 10th term in the geometric sequence.
^An=(-2)(-3)^n-1

A.
–13,122
B.
–39,366
C.
–118,098
D.
–354,294

Question

Use the formula below to find the 10th term in the geometric sequence.
^An=(-2)(-3)^n-1


A.
–13,122
B.
–39,366
C.
–118,098
D.
–354,294

amistre64 · Answer

let n=10 and calculate

anonymous · Answer

just substitute 10 for n

anonymous · Answer

would give me -54, (-2)(3)^10-1

amistre64 · Answer

notation helps, i think that should be:$$A_n=-2~(-3)^{n-1}$$

anonymous · Answer

$$(-2)*(-3)^{10-1}$$
=-39366

amistre64 · Answer

but i could be mistaken

amistre64 · Answer

-^odd = - , and -*- = +  none of the options are a +

anonymous · Answer

I still don't see how that's -39,366

anonymous · Answer

sry that should be a +ve integer

amistre64 · Answer

if we assume$$-2~(-3)^n-1$$we get an option

amistre64 · Answer

but then its not a geometric sequence

anonymous · Answer

oh that should -13122
as the series starts from 0
so tenth digit would be 9
so that would be -2*-3^(9-1)

anonymous · Answer

Ohhhh okay, that makes sense

amistre64 · Answer

the tenth term would still be n=10

amistre64 · Answer

... but your setup does make sense as well :)

anonymous · Answer

if first term of the sequence would be 0
then what would be the 10th term
its 9 obiviously

amistre64 · Answer

different authors start their ns at different places :/

anonymous · Answer

consider $$a _{0}$$ then the 10th term of the sequence would be $$a$$

anonymous · Answer

sry a9