Find the integral int_0^1 1/(5+2x-2x^2) (1+e^(2-4x))dx

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Homework Help Overview

The discussion revolves around evaluating the integral from 0 to 1 of the function 1/(5+2x-2x^2)(1+e^(2-4x)). Participants express their attempts and frustrations in finding a solution using various methods, including integration by parts and substitutions.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants describe attempts to solve the integral using different methods, including substitutions and integration by parts. Some express doubts about the possibility of a closed form solution, while others question the clarity of the problem setup due to a potential typographical error in the variable of integration.

Discussion Status

The discussion includes a mix of attempts to solve the integral and reflections on the complexity of the problem. Some participants have shared their experiences with the integral, noting that it may not have a straightforward solution, while others have indicated that they have found a solution through another participant's work.

Contextual Notes

There is mention of the integral being sourced from an IIT aspirants website, with claims that it remains unsolved, raising questions about its difficulty and the expectations of students encountering such problems.

FedEx
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[tex]\int_0^1\frac{1}{(5+2x-2x^2)(1+e^{2-4x})}dt[/tex]

Believe me. I tried this sum for a good 1 hour.

Tried Parts. All types of substitution. Almost every known method taught to a student of 12th grader. But in vain. A storke of genious. Thats what i need to solve this.

I took the entire denominator for substituion. Just the polynomial. Just the exponential term. In parts i took just the polynomial. Just the exponential term. Everything. No benefits.
 
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And all that while the answer is just
[tex]\frac{1}{(5+2x-2x^2)(1+e^{2-4x})}[/tex].
 


[tex]dt[/tex] not [tex]dx[/tex]. :shy: Foolish to do that to students.
 


Never expected that from you. Its abvious that its a typing mistake. Its dx.

PS I solved the integral by dirk_mec1. Have a look.
 


Hey compuchip...

Sorry. I think i was quite arrogant in the last post.

My apologies.
 


Hi FedEx,

No need to apologize, my reply wasn't very helpful either :smile:
And it's very good that you solved the dirk_mec's integral, although I hope you'll excuse me for not working through the whole calculation :-p That I happen to have this label besides my name by no means implies that I know all the answers or I'm good at everything.

As for your question: I did the integration numerically, and it doesn't look particularly nice. In fact I would really see any good way of solving it, which makes sense since you indicated you have tried all common methods already. I wonder if there is a closed form solution...
 


Hard luck. there's no solution. I saw this sum on an IIT aspirants website. Unsolved. But i am damn sure that even the toughest of IIT Papers doesnot have a sum like this.
 

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