Finding Volume by use of Triple Integrals

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SUMMARY

The discussion focuses on calculating the volume of a solid enclosed by the elliptic paraboloids defined by the equations y = x² + z² and y = 8 - x² - z². The domain of integration is established as 4 = x² + z², with integration limits determined as x² + z² ≤ y ≤ 8 - x² - z², -√(y - z²) ≤ x ≤ √(y - z²), and -2 ≤ z ≤ 2. The integrand for the volume calculation is confirmed to be 1, leading to the volume expression Vol = ∭_R 1 dV. It is recommended to utilize polar coordinates in the xz-plane after performing the dy integral.

PREREQUISITES
  • Understanding of triple integrals in calculus
  • Familiarity with elliptic paraboloids
  • Knowledge of polar coordinates in the xz-plane
  • Proficiency in setting up limits of integration
NEXT STEPS
  • Study the application of triple integrals in volume calculations
  • Learn about the properties and applications of elliptic paraboloids
  • Explore polar coordinates and their use in multivariable calculus
  • Practice setting up and evaluating triple integrals with varying limits
USEFUL FOR

Students and educators in calculus, particularly those focusing on multivariable integration, as well as anyone involved in mathematical modeling of three-dimensional shapes.

maiad
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Homework Statement


Find the Volume of the solid eclose by y=x[itex]^{2}[/itex]+z[itex]^{2}[/itex] and y=8-x[itex]^{2}[/itex]-z[itex]^{2}[/itex]


The Attempt at a Solution



Well know they're both elliptic paraboloids except one is flipped on the xz-plane and moved up 8 units. Knowing this, i equated the two equations and got 4=x[itex]^{x}[/itex]+z[itex]^{2}[/itex] which is the Domain of this volume.

I found the limits of the intergration... x[itex]^{2}[/itex]+z[itex]^{2}[/itex][itex]\leq[/itex]y[itex]\leq[/itex]8-x[itex]^{2}[/itex]-z[itex]^{2}[/itex]...-[itex]\sqrt{y-z^{2}}[/itex][itex]\leq[/itex]x[itex]\leq[/itex][itex]\sqrt{y-z^{2}}[/itex]...-2[itex]\leq[/itex]z[itex]\leq[/itex]2

But my problem now is what am i actually integrating. would it be x[itex]^{2}[/itex]+z[itex]^{2}[/itex]?
 
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maiad said:

Homework Statement


Find the Volume of the solid eclose by y=x[itex]^{2}[/itex]+z[itex]^{2}[/itex] and y=8-x[itex]^{2}[/itex]-z[itex]^{2}[/itex]


The Attempt at a Solution



Well know they're both elliptic paraboloids except one is flipped on the xz-plane and moved up 8 units. Knowing this, i equated the two equations and got 4=x[itex]^{x}[/itex]+z[itex]^{2}[/itex] which is the Domain of this volume.

I found the limits of the intergration... x[itex]^{2}[/itex]+z[itex]^{2}[/itex][itex]\leq[/itex]y[itex]\leq[/itex]8-x[itex]^{2}[/itex]-z[itex]^{2}[/itex]...-[itex]\sqrt{y-z^{2}}[/itex][itex]\leq[/itex]x[itex]\leq[/itex][itex]\sqrt{y-z^{2}}[/itex]...-2[itex]\leq[/itex]z[itex]\leq[/itex]2

But my problem now is what am i actually integrating. would it be x[itex]^{2}[/itex]+z[itex]^{2}[/itex]?

No. The integrand would be ##1##.$$
Vol = \iiint_R 1\, dV$$And I would suggest you using polar coordinates in the ##xz## plane after you do the ##dy## integral.
 

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