Question

What is the seventh term of the sequence 1, 3, 9, 27, ...?

81
243
729
2187

Answer 1

What is 27/9 ?

Answer 2

3 @tHe_FiZiCx99

Answer 3

Yes, lol

So what is 9/3 ?

Answer 4

1 @tHe_FiZiCx99

Answer 5

9/3 is 1 ??! O_O

Answer 6

yes?? @tHe_FiZiCx99

Answer 7

9 DIVIDED BY 3 IS 1??

Answer 8

-3??

Answer 9

Perhaps someone intended that to be a joke and I was too slow to get it. :)

Answer 10

I got 1

Answer 11

81

Answer 12

No, its 3

and 3/1 is 3 xD so their common ratio is 3

So easily plug in for: f(n) = f(1) • r^n-1,

Plug in any number you want to find, I'll find the 6th term.

f(6) = f(1) • 3^6-1

f(6) = f(1) • 3^5
f(6) = f(1) • 243
3 • 243

f(6) = 729

Answer 13

a(n) = 3^(n-1) for all real numbers n

Answer 14

My bad, f(1) = 1

1 * 243 = 243

f(6) = 243

f(7) = 729 lol now there's your answer :#

Answer 15

larryboxaplenty: Great that you could come up with such an appropriate formula!! As for n values, though, wouldn't the domain be "integers starting with 1", and not "all real n"?