Summing an infinite series question

In summary, the problem is to find the sum of two infinite series, Ʃ[n=0 to ∞] ((2^n + 3^n)/6^n) and Ʃ[n=2 to ∞] (2^n + (3^n / n^2)) (1/3^n). The hint suggests splitting them into rational expressions and simplifying, as well as multiplying the bracket out and simplifying. This can be solved using algebra, but it may take a lot of calculations to provide enough evidence for the sums.
  • #1
TheRascalKing
7
0

Homework Statement



I need to fin the sum of the following two infinite series:
1. Ʃ[n=0 to ∞] ((2^n + 3^n)/6^n)

and 2. Ʃ[n=2 to ∞] (2^n + (3^n / n^2)) (1/3^n)

Homework Equations



use the sum Ʃ[n=2 to ∞] (1/n^2) = ∏^2 / 6 as necessary

The Attempt at a Solution



I tried to manipulate them both to make them geometric or telescoping, to no avail. It seems like neither series is telescoping or geometric, so isn't it impossible to definitively sum them?

I started to sum them by adding their partial sums, but they converge very slowly and it would take hundreds of calculations to provide enough evidence for the sums.
 
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  • #2
Hint:

1. Split them into two rational expressions. Simplify (ask what is ##\frac{a^n}{b^n}##?)

2. Multiply the bracket out. Simplify.

It's all just algebra.
 

What is an infinite series?

An infinite series is a mathematical concept that involves adding an infinite number of terms together in a specific order. Each term in the series is related to the previous one, and the sum of all the terms is called the "sum" of the series.

What is the formula for summing an infinite series?

The formula for summing an infinite series is S = a/(1-r), where "a" is the first term in the series and "r" is the common ratio between each term. This formula only applies to geometric series, which have a constant ratio between each term.

Can any infinite series be summed?

No, not all infinite series can be summed. Some series, called divergent series, have sums that approach infinity or negative infinity. These types of series do not have finite sums.

What is the process for summing an infinite series?

The process for summing an infinite series involves identifying the type of series (geometric, arithmetic, etc.), finding the first term and common ratio or difference, and applying the appropriate formula. If the series is divergent, the sum cannot be found.

Why is summing an infinite series important?

Summing an infinite series is important in many areas of science, such as physics, engineering, and finance. It allows for the calculation of values that would otherwise be impossible to determine, and it can help identify patterns and relationships between different mathematical concepts.

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