Question

Consider the sequence 2, 6, 18, 54 ....
Let n= the term number in the sequence
Let A(n)= The value of the nth term of the sequence
4. What is the common ratio in the sequence?

5. Complete each statement
a. A(1) = 2 = 2*3
b. A(2) = 6 = 2*3 = 2*3
c. A(3) = 18 = 2*3*3 = 2*3
d. A(4) = 54 = 2*3*3*3 = 2*3

Answer 1

r = a2/a1 = 6/2 = 3 or
r = a3/a2 = 18/6 = 3 too

Answer 2

wait, lol.. what?

Answer 3

that's to get the common ratio (r)

Answer 4

Oh, I forgot to say, I have number four. I need number five. I'm sorry!

Answer 5

what do you want for no 5 ? lol, a bit confuse what means " complete statement"

Answer 6

See, That's my thing. I'm so confused about that. That is what it says in the book. I think they want to know the exponent of each statement.

Answer 7

maybe like this :
a1 = 2 = 2 * (3)^0 = 2 * 3^(1 - 1)
a2 = 6 = 2 * (3)^1 = 2 * 3^(2 - 1)
a3 = 18 = 2 * (3)^2 = 2 * 3^(3 - 1)
a4 = 54 = 2 * (3)^3 = 2 * 3^(4 - 1)
so on ......
we get the general formula of this sequence :
an = a1 * r^(n-1)

Answer 8

known a1 = 2 and r = 3, so we get
an = a1 * r^(n-1) = 2 * 3^(n-1)
with a1 = 1st term
r = ratio

Answer 9

I think that's right, You're awesome! Thanks bunches! I'll tell you how I do! :)

Answer 10

wlcm :D