Finding Volume of Tetrahedron Using Triple Integral

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SUMMARY

The discussion centers on using a triple integral to find the volume of a tetrahedron defined by the coordinate planes x=0, y=0, z=0, and the plane described by the equation 2x+y+z=0. The integrand is the constant function f(x,y,z)=1, and the integration limits are derived from the plane's equation. However, the conclusion reached is that the volume is zero due to the plane not intersecting the first octant, indicating a potential error in the problem statement. The correct formulation requires a positive constant on the right side of the plane's equation to yield a valid tetrahedron.

PREREQUISITES
  • Understanding of triple integrals in multivariable calculus
  • Familiarity with the concept of tetrahedrons and their geometric properties
  • Knowledge of coordinate planes and intercepts
  • Ability to manipulate and interpret equations of planes in three-dimensional space
NEXT STEPS
  • Review the principles of triple integrals in calculus
  • Study the geometric properties of tetrahedrons and their volume calculations
  • Learn how to determine intercepts of planes in three-dimensional geometry
  • Examine examples of correctly formulated problems involving volume in the first octant
USEFUL FOR

Students studying multivariable calculus, educators teaching geometric applications of integrals, and anyone seeking to understand the volume calculations of three-dimensional shapes using integrals.

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Homework Statement


use triple integral to find the volume of tetrahedron enclosed by the coordinat planes "x=o , y=0 , z=0" and the plane 2x+y+z=0


Homework Equations





The Attempt at a Solution



I will integrate the constant function f(x,y,z)=1 by the order : dzdydx

the equation will be : z=-2x-y
so the limits for the inner integral will be from 0 to -2x-y

when z=0 ---> y=-2x
so the limits for the middle integral will be from 0 to -2x

THE PROBLEM HERE IS THAT
when z=0,y=0 ---> x=0 .. !
so the limits for the outer integral will be from 0 to 0 .. !
and this means the triple integral will be 0 .. !
so there is no volume ??!
 
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I think there is a mistake in the plane's equation, right ?
If I find the x&y&z intercepts, all will be (0,0,0)
so there is no plane !
Right?
 
These type of homework problems typically ask for the volume in the first octant ...

Your plane doesn't pass through the first octant because of the 0 on the right side of the equation. To get three positive intercepts you need a positive number on the right, then it will form a tetrahedron with the coordinate planes. Check the problem is copied correctly.
 

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