Compute the area under the curve

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Homework Help Overview

The discussion revolves around computing the area under a curve defined by the equation (x^3+y^3)^2=x^2+y^2, with an emphasis on the constraints x>0 and y>0. The problem involves transforming the equation into polar coordinates and evaluating the corresponding integral.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss transforming the equation into polar coordinates and the challenges associated with integrating the resulting expression. There is also a question raised about the clarity of the region described by the "area under the curve."

Discussion Status

Some participants have provided guidance on the integral setup and noted discrepancies in the results obtained. There is an acknowledgment of a potential factor that may have been overlooked in the calculations, but no consensus on the final result has been reached.

Contextual Notes

Participants are working under the condition that x and y are both greater than zero, which influences the limits of integration and the interpretation of the area being computed.

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Homework Statement


Hi everyone,
can you give me some hint to solve this? please

Compute the area under the curve:

Homework Equations


[tex](x^3+y^3)^2=x^2+y^2[/tex]

The Attempt at a Solution


I've been trying to transform it into polar coordinates, but I've finished when I get the equation for the radius:
[tex]r^2=1/((\cos(\theta))^3+(\sin(\theta))^3)[/tex],
because then I get the integral which should not be easily integrated (of course I've compute with Jacobian)

thanks for yout attention
 
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Have you looked at the graph? It isn't even clear what region the "area under the curve" describes.
 


I am sorry, I forgot add this condition: [tex]x>0, y>0[/tex], so then I will get the integral in this case:
[tex] \int\limits_{0}^{\pi/2}(\int\limits_{0}^{\frac{1}{\sqrt{\cos^3\alpha+\sin^3\alpha}}}r\,dr)\,d\alpha[/tex],
which results to [tex]1/3 (\pi+2 \sqrt{2} \tanh^{-1}(1/\sqrt{2}))[/tex], but it's little bit different form the correct result which is [tex]\frac{\pi}{6}+\frac{\sqrt{2}}{3}\ln(1+\sqrt{2})[/tex]
 


Your integral looks OK but your answer is off by a factor of 1/2. You probably dropped it somewhere in the calculation.
 


Yes, you're right. l forget 1/2 in front of integral, then the results are same:
1.8781645380502384306795745680939249649333168829204582775232678988974988081580885734995703727615411934.
Thanks for your time.
 

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