Visualizing a Triple Integral Bounded by Planes

arl146
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Homework Statement


the function is xyz2

V is bounded by y=1-x, z=0, and z=y.


The Attempt at a Solution



the limits are:

x is from -1 to 1 ?
y is from 0 to (1-x^2) ?
z is from 0 to y ?

the question asks for a picture ... how should that look? there are points on (1,0,0), (-1,0,0), (0,0,1) and (0,1,0) ?
 
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You need one more bound.
This is likely x=c.
c is come constant
 
i don't get that, i mean like how that helps
 
What you are likely to get is a tetrahedron, which requires 4 faces.
The 4 faces are your 4 bounds, which are planes.
But you have wrote 3 bounds, what about the 4th?
 
arl146 said:

Homework Statement


the function is xyz2

V is bounded by y=1-x, z=0, and z=y.


The Attempt at a Solution



the limits are:

x is from -1 to 1 ?
y is from 0 to (1-x^2) ?
z is from 0 to y ?

the question asks for a picture ... how should that look? there are points on (1,0,0), (-1,0,0), (0,0,1) and (0,1,0) ?
Draw a graph. x is from -1 to 1 so draw two vertical lines at x=-1 and x= 1. y if from 0 to 1- x^2 so draw the the line y= 0 and the parabola y= 1- x^2. The region to be integrated is inside that parabola above y= 0. Finally, the plane z= y crosses the y-axis up to (x, 1, 1) and your three dimensional region comes up to that. As Quinzio said, you need another bound on z or that region is not bounded. As it is, z could go up from that plane to infinity of down to negative infinity. Is there another limit, perhaps 0, on the z-integration?
 
Well I just gave what the problem gave. The upperimit for z is y?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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