Sketching and Calculating the Volume of Solid E

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The discussion revolves around sketching the solid E defined by the cylinder x = y^2 and the planes z = 3 and x + z = 1, with participants struggling to visualize the enclosed volume. One contributor expresses difficulty in obtaining a closed surface, suggesting that a different equation might lead to a clearer understanding. Clarifications about the equations involved, particularly the distinction between x = y^2 and y = x^3, are made to aid in the sketching process. The need for an upper limit on x is highlighted, indicating that without it, the solid cannot be properly defined. Overall, the conversation emphasizes the importance of accurately interpreting the boundaries to successfully sketch and calculate the volume of the solid.
kieranl
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Homework Statement


Sketch the solid E bounded by the cylinder x = y^2 and the planes z = 3 and x + z = 1, and write down its analytic expression. Then, use a triple integral to find the volume of E.

The Attempt at a Solution


Was wondering if someone could have a go at drawing this sketch? In mine, I thought i did it right but can't seem to obtain an enclosed surface. If x+z=1 was rather x-z=1 i would be able to but can't so far?
 
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The plane x+ z= 1 crosses the plane z= 3 when x+ 3= 1 or the line x= -2, z= 3, y= t. It crosses the cylinder x= y^2 in the line x= t^2, y= t, z= 1- x= 1- t^2.

I wonder if you weren't confusing x= y^2 with the y= x^3.
 
I don't think you NEED to graph this.

y=(plus/minus) sqrt(x)

If that helps.

The range is x>0, so sqrt(x) is real.

If x>0, which is on top, z=3 or z=1-x?EDIt: Is there an upper bound on x?
 
wat i have done is drawn the cylinder x = y^2 in the x-y plane and extended it along the z plane. Then i drew the z=3 plane and then drew a line z=1-x and it extended it along the y plane. But this does not end up enclosing a solid
 
kieranl said:
wat i have done is drawn the cylinder x = y^2 in the x-y plane and extended it along the z plane. Then i drew the z=3 plane and then drew a line z=1-x and it extended it along the y plane. But this does not end up enclosing a solid

You are right, I think. There must be an upper x-limit for this to be a solid. Maybe, you have accidentally skipped some information.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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