How do you find the indefinite integral of xsinx

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Discussion Overview

The discussion revolves around finding the indefinite integral of the function xsin(x) with respect to x. Participants explore the method of integration by parts, share their understanding of integration concepts, and clarify their current level of calculus knowledge.

Discussion Character

  • Homework-related
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • David expresses curiosity about how to find the indefinite integral of xsin(x).
  • Daniel suggests using the integration by parts method and provides the formula for it.
  • David indicates he is not familiar with integration by parts and has not yet reached that topic in his calculus class.
  • Daniel questions David's motivation for asking about the integral if he has not covered the topic yet.
  • Another participant explains how to apply the integration by parts formula to the specific problem, suggesting to set u = x and dv/dx = sin(x).
  • David mentions he has learned some integration techniques but has not encountered integration by parts in his coursework yet.
  • Daniel comments on the relationship between integration by parts and the product rule of differentiation, suggesting it may be easier than substitution.
  • David acknowledges that he understands the explanation provided about integration by parts.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the use of integration by parts, as David has not yet learned this method in his class, while Daniel and others assume familiarity with it. The discussion reflects varying levels of understanding and knowledge of calculus concepts.

Contextual Notes

David's understanding of integration is limited to what has been covered in his calculus class, which may not include integration by parts yet. There is a mention of a specific textbook where this topic is introduced later in the curriculum.

Who May Find This Useful

Students learning calculus, particularly those interested in integration techniques and the application of integration by parts.

laker88116
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I am just curious I was thinking about this and if anyone could explain I would appreciate it. I am curious to know how to find the indefinite integral of xsinx with respect to x.

Thanks, David
 
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Are u familiar to the part integration method...?If so,then do it...

Daniel.
 
im not, i did a lot bit of research however i am having difficulty comprehending it, I am in calculus ab now, we have yet to reach that if it is in our agenda
 
Since part integration is the first method of integration one learns,i suspect you haven't reached indefinite integration at all.In which case,why bother...?Is it curiosity,or what...?

Daniel.
 
The integration by parts formula is:

[tex]\int u \frac{dv}{dx} dx = uv - \int \frac{du}{dx} v dx[/tex].

In your problem, put

[tex]u = x, \qquad \frac{dv}{dx} = \sin x[/tex].

Now find [itex]du/dx[/itex] and [itex]v[/itex], then plug them into the formula above. Do the second integration, and you're done.
 
ive reached integration, i can integrate like 2sin2x when using substitution as long as the constant cancels out from du, in my book, thomas/finney 9th edition calculus, it isn't introduced until the latter part of the book, and since my class is only for the ap test, its not like we will get that far anyway i don't think and I am just curious, i looked in the book but its past me
 
ok that helps i get it that way, thanks
 
Part integration uses product rule of differentiation for proving.I think that's a little easier than substitution,which would require chain rule for proving...:wink:

Daniel.

P.S.I think someone else offered the solution.
 
thats it, it slipped my mind i couldn't remember what its called, but yeah, chain rule is what i was getting at, we just haven't done integration by parts yet
 

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