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U1 = a = 21

U6 = ar5 = 352947

where Un is the nth term, with first term, a, and commn ratio r.

Dividing the second equation by the first, r5 = 16807

Taking the fifth root, r = 7.

The S6 = a*(r6 - 1)/(r - 1) = 21*(76-1)/(7-1) = 411768

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How do you find the first term of a geometric series?

The answer depends on what information you have been provided with.


What are the formulas for geometric sequences and series?

In a geometric sequence, each term is found by multiplying the previous term by a constant ratio ( r ). The ( n )-th term can be expressed as ( a_n = a_1 \cdot r^{(n-1)} ), where ( a_1 ) is the first term. For the sum of the first ( n ) terms of a geometric series, the formula is ( S_n = a_1 \frac{1 - r^n}{1 - r} ) for ( r \neq 1 ), while for an infinite geometric series, if ( |r| < 1 ), the sum is ( S = \frac{a_1}{1 - r} ).


What does an equal in geometric series?

Geometric series may be defined in terms of the common ratio, r, and either the zeroth term, a(0), or the first term, a(1).Accordingly,a(n) = a(0) * r^n ora(n) = a(1) * r^(n-1)


What does summation of infinite series?

The summation of a geometric series to infinity is equal to a/1-rwhere a is equal to the first term and r is equal to the common difference between the terms.


What is the difference between an arithmetic series and a geometric series?

An arithmetic series is the sequence of partial sums of an arithmetic sequence. That is, if A = {a, a+d, a+2d, ..., a+(n-1)d, ... } then the terms of the arithmetic series, S(n), are the sums of the first n terms and S(n) = n/2*[2a + (n-1)d]. Arithmetic series can never converge.A geometric series is the sequence of partial sums of a geometric sequence. That is, if G = {a, ar, ar^2, ..., ar^(n-1), ... } then the terms of the geometric series, T(n), are the sums of the first n terms and T(n) = a*(1 - r^n)/(1 - r). If |r| < 1 then T(n) tends to 1/(1 - r) as n tends to infinity.

Related Questions

What does Geometric Series represent?

A geometric series represents the partial sums of a geometric sequence. The nth term in a geometric series with first term a and common ratio r is:T(n) = a(1 - r^n)/(1 - r)


How do you find the first term of a geometric series?

The answer depends on what information you have been provided with.


What are the formulas for geometric sequences and series?

In a geometric sequence, each term is found by multiplying the previous term by a constant ratio ( r ). The ( n )-th term can be expressed as ( a_n = a_1 \cdot r^{(n-1)} ), where ( a_1 ) is the first term. For the sum of the first ( n ) terms of a geometric series, the formula is ( S_n = a_1 \frac{1 - r^n}{1 - r} ) for ( r \neq 1 ), while for an infinite geometric series, if ( |r| &lt; 1 ), the sum is ( S = \frac{a_1}{1 - r} ).


A geometric series has first term 4 and its sum to infinity is 5 Find the common ratio?

1/8


How is emailing a joke like a geometric series?

Emailing a joke is like a geometric series because each time the joke is passed along, it has the potential to reach more and more people exponentially, similar to how each term in a geometric series is multiplied by a constant factor. Just as the sum of a geometric series can grow rapidly, the spread of a joke can escalate quickly as recipients share it with others. Additionally, the initial joke serves as the first term, while the act of forwarding it represents the common ratio that drives its expansion.


What does an equal in geometric series?

Geometric series may be defined in terms of the common ratio, r, and either the zeroth term, a(0), or the first term, a(1).Accordingly,a(n) = a(0) * r^n ora(n) = a(1) * r^(n-1)


The fourth term of a geometric sequence is -64 the product of the first and third term is 16?

the series can be 1,-4,16,-64


What does summation of infinite series?

The summation of a geometric series to infinity is equal to a/1-rwhere a is equal to the first term and r is equal to the common difference between the terms.


What is the difference between an arithmetic series and a geometric series?

An arithmetic series is the sequence of partial sums of an arithmetic sequence. That is, if A = {a, a+d, a+2d, ..., a+(n-1)d, ... } then the terms of the arithmetic series, S(n), are the sums of the first n terms and S(n) = n/2*[2a + (n-1)d]. Arithmetic series can never converge.A geometric series is the sequence of partial sums of a geometric sequence. That is, if G = {a, ar, ar^2, ..., ar^(n-1), ... } then the terms of the geometric series, T(n), are the sums of the first n terms and T(n) = a*(1 - r^n)/(1 - r). If |r| < 1 then T(n) tends to 1/(1 - r) as n tends to infinity.


A geometric progression has a common ratio -1/2 and the sum of its first 3 terms is 18. Find the sum to infinity?

The sum to infinity of a geometric series is given by the formula Sāˆž=a1/(1-r), where a1 is the first term in the series and r is found by dividing any term by the term immediately before it.


What is the formula for the geometric progression with the first 3 terms 4 2 1?

The nth term of the series is [ 4/2(n-1) ].


The sum to three terms of geometric series is 9 and its sum to infinity is 8. What could you deduce about the common ratio. Why. Find the first term and common ratio?

The geometric sequence with three terms with a sum of nine and the sum to infinity of 8 is -9,-18, and 36. The first term is -9 and the common ratio is -2.