Problem solving this volume using Jacobi's Determinant

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SUMMARY

The discussion focuses on calculating the volume of a solid defined by the equation 3x + 4y + 2z = 10 as the ceiling and various cylindrical surfaces as the floor. The integral setup is established as ∫∫z(x,y)dxdy = Volume, leading to the expression ∫∫(3 - 1.5x - 0.5y)dxdy. The participants emphasize the complexity of determining the limits for integration and suggest using a change of variables along with Jacobi's determinant to simplify the process. Visual aids are recommended to better understand the solid's shape and integration limits.

PREREQUISITES
  • Understanding of double integrals in multivariable calculus
  • Familiarity with Jacobi's determinant for variable transformations
  • Knowledge of cylindrical surfaces and their equations
  • Ability to visualize three-dimensional solids and their projections onto the xy-plane
NEXT STEPS
  • Study the method of change of variables in double integrals
  • Learn how to compute Jacobi's determinant for transformations
  • Explore visualizing solids in three dimensions using software tools like GeoGebra
  • Practice solving volume problems involving multiple surfaces and integration limits
USEFUL FOR

Students and educators in multivariable calculus, mathematicians dealing with volume calculations, and anyone interested in mastering integration techniques involving complex geometric shapes.

JorgeM
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Homework Statement


Find the value of the solid's volume given by the ecuation 3x+4y+2z=10 as ceiling,and the cilindric surfaces
2x^2=y
x^2=3*y
4y^2=x
y^2=3x
and the xy plane as floor.

The Attempt at a Solution


I know that we have to give the ecuation this form:
∫∫z(x,y)dxdy= Volume
So, in fact we have to solve:
∫∫ ( 3 - 1.5x - .5y ) dxdy but actually it is easier to do variables' change because of the fact that the limits are to tricky to solve.

I get so confused when I try to suppose a good change and use in the Jacobi's determinant.
Hope you could help my because I got so confused :(

Thanks for your advise.
 
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Just to visualize your solid. On the (x,y) plane it looks like the grey area in

upload_2018-12-12_5-33-47.png
where the blue line is from the ceiling, a pyramid which crosses the z axis at 5 indicated by the pink area.

You can try to figure out your limits for the integrals with this picture in mind.
 

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