Integrating over Region A: Calculating the Volume of a Cone

WannaBe22
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Homework Statement


Let A be the region that in space bounded by the balls:
x^2 +y^2 + z^2 =1 , x^2 +y^2 +z^2 =4 , above the plane z=0 and inside the cone z^2 = x^2 +y^2.

A. Write the integral \int \int \int_{A} f(x,y,z) dxdydz in the form:
\int \int_{E} (\int_{g^1(x,y)}^{g^2(x,y)} f(x,y,z) dz) dxdy when :
A=( (x,y,z) | (x,y) \in E, g^1(x,y) \le z \le g^2(x,y) ) ...

B. Find the volume of A (not necessarily using part A).

Hope you'll be able to help me in this... I think the main problem is that I can't figure out how A looks like... There is also a hint that one of the functions g1 or g2 should be defined at a split region... I can't figure out how this cone looks like and how I can describe A as equations ...


Thanks in advance!


Homework Equations





The Attempt at a Solution

 
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no consider a slice for a given z, you have y^2 + x^2 = z^2, which is an equation for a circle in x & y - what is the radius?

the 2nd part will be much easier to do in spherical coordinates...
 
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