Answer :
Answer: The sum of the first 10 terms of the given geometric sequence is 3069.
Step-by-step explanation:
A geometric sequence is a sequence of numbers such that any two consecutive terms are in a constant ratio.
The first term of the given sequence is 3 and the common ratio is 2 (6/3 = 12/6 = 24/12 = ...).
To find the sum of the first 10 terms of a geometric sequence, we can use the formula:
S = a(1 - r^n)/(1 - r)
where a is the first term, r is the common ratio and n is the number of terms.
So for this geometric sequence:
S = 3(1 - 2^10)/(1 - 2) = 3(1 - 1024)/(-1) = 3(-1023)/(-1) = 3069
Explanation: By using the formula for the sum of a geometric sequence, the sum of the first 10 terms of the sequence was found by substituting the first term, common ratio and number of terms into the formula.
Answer:
C) 3069
Step-by-step explanation:
A geometric series is the sum of the terms of a geometric sequence.
[tex]\boxed{\begin{minipage}{7 cm}\underline{Sum of the first $n$ terms of a geometric series}\\\\$S_n=\dfrac{a(1-r^n)}{1-r}$\\\\where:\\\phantom{ww}$\bullet$ $a$ is the first term. \\ \phantom{ww}$\bullet$ $r$ is the common ratio.\\\end{minipage}}[/tex]
Given geometric sequence:
- {3, 6, 12, 24, 48...}
From inspection of the sequence, the first term is 3:
[tex]\implies a=3[/tex]
To find the common ratio, divide consecutive terms:
[tex]\implies r=\dfrac{a_2}{a_1}=\dfrac{6}{3}=2[/tex]
To find the sum of the first 10 terms, substitute the found values of a and r together with n=10 into the geometric series formula:
[tex]\implies S_{10}=\dfrac{3(1-2^{10})}{1-2}[/tex]
[tex]\implies S_{10}=\dfrac{3(1-1024)}{1-2}[/tex]
[tex]\implies S_{10}=\dfrac{3(-1023)}{-1}[/tex]
[tex]\implies S_{10}=\dfrac{-3069}{-1}[/tex]
[tex]\implies S_{10}=3069[/tex]
Therefore, the sum of the first 10 terms of the given geometric sequence is:
- 3069