Problem

Points: 0 of 10 Find the sum of the first 13 terms of the geometric sequence shown below. \[ 3,12,48,192, \ldots \] The sum of the first 13 terms is $\square$.

Solution

Step 1 :The given sequence is a geometric sequence. In a geometric sequence, each term after the first is found by multiplying the previous term by a fixed, non-zero number called the ratio. In this case, the ratio is 4 (12/3 = 4, 48/12 = 4, 192/48 = 4).

Step 2 :The sum of the first n terms of a geometric sequence can be found using the formula: \(S_n = a * (1 - r^n) / (1 - r)\) where: \(S_n\) is the sum of the first n terms, \(a\) is the first term, \(r\) is the ratio, and \(n\) is the number of terms.

Step 3 :In this case, \(a = 3\), \(r = 4\), and \(n = 13\).

Step 4 :Let's plug these values into the formula and calculate the sum.

Step 5 :Final Answer: The sum of the first 13 terms is \(\boxed{67108863}\).

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Source: https://solvelyapp.com/problems/8dn6RGzK5m/

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