Question

Which of the following is the formula for this geometric sequence?
1, -3, 9, -27,...

Answer 1

ok for this we have:

Answer 2

the multiplying ratio as -1/3

Answer 3

There are answer choices

Answer 4

if you want the sum you havesummation to give 1/(1/1+1/3) = 3/4

Answer 5

whoa, sorry r = -3

Answer 6

you cannt use the summation i used above! sorry for the error. but each term a1=1, a2 = -3, a3=9
so the i+1st term is -1/3 i

Answer 7

does this make sensE?

Answer 8

hoe it helped!

Answer 9

Is an answer choice -1(3)^n-1

Answer 10

yes, that would be it

Answer 11

yay