Find The Sum ∑(1/[3^n+√(3^(2017)]

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In summary, the number 2017 in the equation serves as the exponent of 3 in the denominator, likely chosen for its complexity. The value of n determines the number of terms in the sum, with a larger n resulting in a larger sum. The equation can be simplified using the formula for the sum of a geometric series, resulting in a final value dependent on n. The value of √(3^2017) does not affect the sum significantly. This equation is useful in various scientific fields for studying geometric series and modeling real-world phenomena.
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lfdahl
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Evaluate the sum:$$\sum_{n=0}^{2017}\frac{1}{3^n+\sqrt{3^{2017}}}$$
 
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  • #2
lfdahl said:
Evaluate the sum:$$\sum_{n=0}^{2017}\frac{1}{3^n+\sqrt{3^{2017}}}$$
$$\sum_{n=0}^{2017}\frac{1}{3^n+\sqrt{3^{2017}}}=\frac{1}{1+\sqrt{3^{2017}}}+\frac{1}{3+\sqrt{3^{2017}}}+\frac{1}{3^2+\sqrt{3^{2017}}}+\cdots+\frac{1}{3^{2015}+\sqrt{3^{2017}}}+\frac{1}{3^{2016}+\sqrt{3^{2017}}}+\frac{1}{3^{2017}+\sqrt{3^{2017}}}$$

Observe that taking the first and last terms;

$$\frac{1}{1+\sqrt{3^{2017}}}+\frac{1}{3^{2017}+\sqrt{3^{2017}}}=\frac{1}{1+\sqrt{3^{2017}}}+\frac{1}{\sqrt{3^{2017}}(1+\sqrt{3^{2017}})}=\frac{1}{\sqrt{3^{2017}}}$$

Generally this holds for all $i$ and $n-i$ terms taken in pairs. Thus our sum reduces to,

$$\sum_{n=0}^{2017}\frac{1}{3^n+\sqrt{3^{2017}}}=\left(\frac{2018}{2}\right)\frac{1}{\sqrt{3^{2017}}}=\frac{1009}{\sqrt{3^{2017}}}$$
 
  • #3
Sudharaka said:
$$\sum_{n=0}^{2017}\frac{1}{3^n+\sqrt{3^{2017}}}=\frac{1}{1+\sqrt{3^{2017}}}+\frac{1}{3+\sqrt{3^{2017}}}+\frac{1}{3^2+\sqrt{3^{2017}}}+\cdots+\frac{1}{3^{2015}+\sqrt{3^{2017}}}+\frac{1}{3^{2016}+\sqrt{3^{2017}}}+\frac{1}{3^{2017}+\sqrt{3^{2017}}}$$

Observe that taking the first and last terms;

$$\frac{1}{1+\sqrt{3^{2017}}}+\frac{1}{3^{2017}+\sqrt{3^{2017}}}=\frac{1}{1+\sqrt{3^{2017}}}+\frac{1}{\sqrt{3^{2017}}(1+\sqrt{3^{2017}})}=\frac{1}{\sqrt{3^{2017}}}$$

Generally this holds for all $i$ and $n-i$ terms taken in pairs. Thus our sum reduces to,

$$\sum_{n=0}^{2017}\frac{1}{3^n+\sqrt{3^{2017}}}=\left(\frac{2018}{2}\right)\frac{1}{\sqrt{3^{2017}}}=\frac{1009}{\sqrt{3^{2017}}}$$

What a nice solution, Sudharaka! Thankyou very much for your participation
 

FAQ: Find The Sum ∑(1/[3^n+√(3^(2017)]

What is the significance of the number 2017 in the equation?

The number 2017 is the exponent of 3 in the denominator of the equation. It was likely chosen because it is a prime number, making the calculation more complex.

How does the value of n affect the sum?

The value of n determines the number of terms in the sum. As n increases, the number of terms also increases, resulting in a larger sum.

Can the equation be simplified?

Yes, the equation can be simplified by using the formula for the sum of a geometric series. This will result in a final value that is a function of n.

How does the value of √(32017) affect the sum?

The value of √(32017) does not affect the sum as it is a constant value. It simply adds a small amount to the denominator of each term, making the overall sum slightly smaller.

What is the purpose of this equation in scientific research?

This equation may be used in various fields such as mathematics, physics, and computer science to study the behavior of geometric series and their applications. It may also be used to model real-world phenomena that follow a geometric pattern.

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