Waste less time on Facebook — follow Brilliant.
×

How to start?

\( \displaystyle \sum_{n=1}^{\infty} \dfrac{1}{n^2} \cos\Big(\dfrac{9}{n\pi + \sqrt{(n\pi)^2 - 9}}\Big) = - \dfrac{\pi^2}{12e^3}\)

Note by Megh Choksi
2 years, 4 months ago

No vote yet
1 vote

Comments

Sort by:

Top Newest

Can you approximate \( n \pi - \sqrt{ ( n \pi ) ^2 - 9 } \) as \(n\) gets large? Use Big-O notation if you are familiar with that.

Are you sure that there is an \( e^3 \) in there?

Also, please use distinct values for your indices. You cannot take the sum of the variable \(n\) , as it goes from 1 to \(n\). Calvin Lin Staff · 2 years, 4 months ago

Log in to reply

@Calvin Lin I am not familiar with that , I am sure that this is the question . Unable to solve that's why shared it and mentioned some brilliant members.

In a magazine - Mathematics today I saw it , Chapter - definite integration , section - Sandwich theorem Megh Choksi · 2 years, 4 months ago

Log in to reply

Shivang Jindal Ronak Agarwal Pratik Shastri Sudeep Salgia @Rube Megh Choksi · 2 years, 4 months ago

Log in to reply

What is p? Abhay Agnihotri · 2 years, 4 months ago

Log in to reply

@Abhay Agnihotri sorry its \(\pi\) Megh Choksi · 2 years, 4 months ago

Log in to reply

×

Problem Loading...

Note Loading...

Set Loading...