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NO LINKS!! Find the specified term of the geometric sequence.

a6: a1 = 3, a2= 18, a3= 108, . . .

a6=

User Emerita
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2 Answers

2 votes

Answer:


a_(6) = 23,328

Explanation:

⭐ Geometric Progression formula:
a_(n) = a_1(b)^(n-1)


  • a_(1) is the first term of the geometric progression

  • b is the common ratio (the number each term gets multiplied by)

  • a_(n) is the notation for which term you are finding, where n is the term number

We are given that
a_(1) = 3. Now, we need to find b.

b is the quotient of
(a__3)/(a__2).


  • (a_3)/(a_2)\\ \\(108)/(18)\\= 6

  • b = 6

Let's substitute the first term and common ratio into the formula.


a_n = 3(6)^(n-1)

The problem wants us to solve for the 6th term, so we have to substitute 6 for n and solve.


a_6 = 3(6)^(6-1)\\a_6 = 3(6)^5\\a_6 = 3(7,776)\\a_6 = 23,328

User Shaurya Chaudhuri
by
4.2k points
4 votes

Answer:

23328

Explanation:

since it is a geometrics sequence we will use the formula


{ar}^(n - 1)

The first term(a) = 3

The second term = ar = 18

divide the first term and second term to find the common ratio


(t2)/(t1) = (ar)/(a) = (18)/(3)

r = 6

Now lets find the sixth term


t6 = {ar}^(6 - 1)


t6 = {ar}^(5)

by substituting for the values


t6 = 3 * {6}^(5)

= 3 × 7776

= 23328

i hope this helped

User Infiltrator
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