Answer:
A9 = 393216
Step-by-step explanation:
the first thing that will help you solve this question is finding the common ratio between each terms
the first thing that I like to do that usually helps is to take the second term (-24) and divide it by the first term (6) --> this will usually help you spot the common ratio fairly quickly
in your case, the common ratio is -4
- you can also check this by following my note above and then multiplying the second term by the common ratio to see if it matches the third term, which it does!
so now you can go about this two different ways
1. solve directly for the 9th term
2. use the nth term formula for geometric sequences
METHOD 1:
if you continue to multiply by -4 to solve for each term you would end up with:
6, -24, 96, -384, 1536, -6144, 24576, -98304, 393216
and you will recieve 393216 as your answer
METHOD 2:
the nth term formula is An = A1*r^(n-1)
where An = the nth term of the sequence
A1 = first term of the sequence (6)
and r = common ratio
using this formula, you would get:
A9 = 6(-4)^8
A9 = 393216
I hope this helped :)
