Solving an Intriguing Integral: x-1 in the First Quadrant

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SUMMARY

The integral problem discussed involves calculating the double integral \(\int\int_R (x-1) dA\) over the region \(R\) in the first quadrant, bounded by the curves \(y=x\) and \(y=x^3\). The correct bounds for integration are established as \(\int_{x=0}^1\int_{y=x^3}^x (x-1) dy dx\). The calculated result of the integral is \(-\frac{7}{60}\), which has been verified using a Computer Algebra System (CAS). There is a discrepancy with the textbook answer of \(-\frac{1}{2}\), suggesting a potential misprint or misunderstanding of the bounds.

PREREQUISITES
  • Understanding of double integrals in calculus
  • Familiarity with the concept of regions defined by curves
  • Knowledge of the properties of definite integrals
  • Experience with Computer Algebra Systems (CAS) for verification
NEXT STEPS
  • Review the method for setting up double integrals over bounded regions
  • Study the properties of the curves \(y=x\) and \(y=x^3\) in the first quadrant
  • Learn how to use CAS tools for integral verification
  • Investigate common pitfalls in integral calculus that lead to discrepancies in answers
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Students studying calculus, educators teaching integral calculus, and anyone interested in mastering double integrals and verifying their results using computational tools.

Knissp
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Homework Statement


[tex]\int\int_R x-1 dA[/tex]
R is the region in the first quadrant enclosed between y=x and y=x^3



Homework Equations





The Attempt at a Solution



I set up the bounds as follows: [tex]\int_{x=0}^1\int_{y=x^3}^x x-1 dydx[/tex]

Integrating, I get -7/60, verified with CAS.

I thought this was an easy problem but my answer doesn't match the textbook (-1/2 but could be a misprint, right?) or did I somehow put the bounds of integration wrong?
 
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It looks fine to me.
 
I agree with your answer
 

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