Help with Integration: x^2cos(x^5)dx

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Homework Help Overview

The discussion revolves around the integration of the function x^2 cos(x^5) dx, which is presented as part of a calculus problem. Participants are exploring the complexities of this integral, particularly in the context of reversing the order of integration in a double integral setup.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss various attempts at integration, including integration by parts and the implications of reversing the order of integration. Questions arise regarding the appropriateness of the problem for the stated course level and the original context of the problem.

Discussion Status

The discussion is ongoing, with participants sharing their thoughts on the integration process and questioning the feasibility of solving the integral as presented. Some guidance on reversing the order of integration has been mentioned, but there is no consensus on a solution.

Contextual Notes

There are indications of confusion regarding the original problem's complexity and its suitability for the participants' current coursework. The original poster emphasizes that the problem is from an exam, which adds to the urgency and curiosity surrounding the discussion.

fantomas2005
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can someone integrate that problem

x^2 cos (x^5) dx

i tried integration by parts but i didn't get anything
 
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There might be something wrong with the question if you are in an introductory course

some mess:

f =

x^2*cos(x^5)


>> int(f,x)

ans =

1/10*2^(3/5)*pi^(1/2)*(5/3/pi^(1/2)/x^2*2^(2/5)
*sin(x^5)+5/3/pi^(1/2)/x^2*2^(2/5)*(cos(x^5)
*x^5-sin(x^5))-2/3/pi^(1/2)*x^8*2^(2/5)/(x^5)^(11/10)
*sin(x^5)*LommelS1(1/10,3/2,x^5)-5/3/pi^(1/2)*x^8
*2^(2/5)/(x^5)^(21/10)*(cos(x^5)*x^5-sin(x^5))
*LommelS1(11/10,1/2,x^5))


>> f = x^2*(cos(x))^5

f =

x^2*cos(x)^5


>> int(f,x)

ans =

x^2*(1/5*cos(x)^4*sin(x)+4/15*cos(x)^2*
sin(x)+8/15*sin(x))+2/25*x*cos(x)^5-2/125*
cos(x)^4*sin(x)-272/3375*cos(x)^2*sin(x)-4144/3375*
sin(x)+8/45*x*cos(x)^3+16/15*x*cos(x)
 
no there is nothing wrong with the problem and iam in what called in our country differentiation and integration 2 like calculus 3
and the original problem is from my exam {{ and i didn't solve it but I'm curious }}



given____ { int from 0 to 4 }{int from y^1/2 to 2 } cos(x^5) dx dy ____ reverse the order of integration and evaluate the resulting intgerals .


after reversing , it will be ______ x^2 cos (x^5) dx _______ and the inequalities dosent matter
 
You reversed the order of integration. You intergrate with wrt y first, dydx.
 
Last edited:
so what is the solution of the integration pls
 
Are you sure it was [itex]\cos(x^5)[/itex]? You really couldn't integrate that on a test. The method for reversing the order of integration is fairly simple. You first need to sketch the area of integration on a graph and then find the limits for integrating over y with x constant and then the limits for integrating over x with y constant.
 
i'm absolutely sure that it's int of x^2 cos(x^5) dx

dose anyone have any idea ??
 
What was the original question? We've already proved that the integral you post is too difficult!
 

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