Jacobi Matrix and Multiple Intgrals

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SUMMARY

The discussion focuses on finding a function g: R² → R that satisfies the integral equation ∫₀¹ ∫₀¹ h(x,y)dxdy = ∫₀¹ ∫₀¹ h(y⁵, x³) * g(x,y)dxdy for all integrable functions h over the domain D defined by 0 ≤ x ≤ 1 and 0 ≤ y ≤ 1. The Jacobi matrix for the transformation f(x,y) = (y⁵, x³) has been calculated, yielding a determinant of -15y⁴x³. The change of variables x = u⁵ and y = v³ is suggested to simplify the integral, ensuring the mapping remains within the square D.

PREREQUISITES
  • Understanding of double integrals and their properties
  • Familiarity with the change of variables theorem in calculus
  • Knowledge of Jacobi matrices and determinants
  • Basic concepts of integrable functions over a defined domain
NEXT STEPS
  • Study the change of variables theorem in multivariable calculus
  • Learn about the properties and applications of Jacobi matrices
  • Explore techniques for evaluating double integrals with variable transformations
  • Investigate the implications of determinant values in transformation mappings
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Students and professionals in mathematics, particularly those studying calculus, multivariable functions, and integral transformations, will benefit from this discussion.

Kork
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Homework Statement



Let D be the set of points (x,y) in R^2 for which 0 is ≤ x ≤ 1 and 0 ≤ y ≤ 1. Find a function g: R^2 --> R for which:

∫_0^1 ∫_0^1 h(x,y)dxdy = ∫_0^1∫_0^1 h(y^5, x^3) * g(x,y)dxdy

is true for all functions h: D--> R integrable over D

In the question before this I was asked to find a jacobi matrix and determinant for f(x,y) = (y^5,x^3)

I found that the determinant is -15y^4x^3

Homework Equations




The Attempt at a Solution



∬_D f(x,y)dxdy= ∬_S g(v^5,u^3) * -15y^4x^2

Is this my final result? If not, can I get some help on how to go on?
 
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Kork said:

Homework Statement



Let D be the set of points (x,y) in R^2 for which 0 is ≤ x ≤ 1 and 0 ≤ y ≤ 1. Find a function g: R^2 --> R for which:

∫_0^1 ∫_0^1 h(x,y)dxdy = ∫_0^1∫_0^1 h(y^5, x^3) * g(x,y)dxdy

is true for all functions h: D--> R integrable over D

In the question before this I was asked to find a jacobi matrix and determinant for f(x,y) = (y^5,x^3)

I found that the determinant is -15y^4x^3

Homework Equations




The Attempt at a Solution



∬_D f(x,y)dxdy= ∬_S g(v^5,u^3) * -15y^4x^2

Is this my final result? If not, can I get some help on how to go on?

Your answer shouldn't have 4 variables and needs the integration variables.

Your problem certainly suggests the change of variables ##x=u^5,\ y=v^3##. You need to check that maps the square to the square. Then use your change of variables theorem to express your integral in terms of ##u## and ##v##. Your result should have just ##u## and ##v## variables in it. Of course, they are dummy variables in the final result.
 

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