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Write a formula for the generai term of the geometric sequence. Then use the formula for a n to find ay, the seventh term of the sequence. 1.2,2,4,4.8,9.6

a n =
a 7 =

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Final answer:

The general term (a_n) of the geometric sequence is a_n = a₁ * r^(n-1), where a₁ is the first term and r is the common ratio. Then, a₇, the seventh term of the sequence, can be found using this formula.

Step-by-step explanation:

In a geometric sequence, each term is obtained by multiplying the preceding term by a fixed number called the common ratio.

Given the sequence: 1.2, 2, 4, 4.8, 9.6

We notice that each term is obtained by multiplying the previous term by a constant factor. To find the common ratio (r), we can divide any term by its preceding term. Let's take the ratio of the 4th term to the 3rd term: 4.8 / 4 = 1.2. Hence, the common ratio is 1.2.

The first term (a₁) is 1.2, and the common ratio (r) is also 1.2. Therefore, the general term of the sequence (a_n) can be written as a_n = 1.2 * 1.2^(n-1).

Now, to find the seventh term (a₇), substitute n = 7 into the formula:

a₇ = 1.2 * 1.2^(7-1) = 1.2 * 1.2^6 = 1.2 * 9.1776 ≈ 11.01312.

Thus, the seventh term of the sequence is approximately 11.01312.

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