Integrate (2x^2+1)e^x^2dx ( Wow, seriously?)

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Homework Help Overview

The problem involves integrating the expression (2x^2+1)e^x^2 with respect to x. The subject area is calculus, specifically focusing on integration techniques.

Discussion Character

  • Exploratory, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to use substitution and integration by parts but expresses confusion about the lack of an anti-derivative for e^x^2. They explore a substitution involving u = e^x^2 but become stuck with the resulting expressions. Other participants suggest expanding the integrand and applying integration by parts to simplify the problem.

Discussion Status

Participants are exploring different methods to approach the integration problem. Some guidance has been offered regarding expanding the integrand and focusing on one term for integration by parts. There is an acknowledgment of alternative strategies that may simplify the process.

Contextual Notes

The original poster mentions feeling overwhelmed by the complexity of the integrand and the limitations of their attempted methods. There is a sense of uncertainty regarding the best approach to take.

RoganSarine
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Homework Statement



Integrate: (2x^2+1)e^x^2dx

Homework Equations





The Attempt at a Solution



I don't even know where to start , I either got to do this by basic substitution or by parts. Basic substitution doesn't help for obvious reasons, so I thought I'd do it by parts, but that would get completely messed up based upon the e^x^2 not having any anti-derivative, so I'd need basic substitution to get rid of it.

I thought of making:

u = e^x^2
ln|u| = x^2
√ln|u| = x
du = 2xe^x^2 dx

Therefore, my equation would be:

(2ln|u| + 1)/(2√[ln|u|]) du

Then I thought about breaking that up:

integrate: (2ln|u|)/(2√[ln|u|]) + 1/(2√[ln|u|])

Simplified to...

(ln|u|)/(√[ln|u|]) + 1/(2√[ln|u|])

Annnndd... now I'm stuck again because that square root is basically the most evilest thing on the entire planet. It limits partial fractions, I can't exactly do trig substitution, and the fraction kills by parts.
 
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Expand out the brackets of the integrand to get two terms, then try to do by parts on the first term only. Hint: dv = 2x e^{x^2}dx.
 
Last edited:
huh... This looks a lot simpler than my way... Let's see if I can finish it :P
 
Huh, wow... Thanks, I didn't even THINK about being able to cancel the integrals that result.
 

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