Triple Integral: Volume of a Solid

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The discussion focuses on using a triple integral to find the volume of a solid defined by a cylinder and two planes. The bounds for the integral are established as -3 ≤ y ≤ 3 and 1 ≤ z ≤ 16 - y, with x bounded by -√(9 - y²) and √(9 - y²). It is noted that the planes do not intersect within the cylinder, simplifying the setup of the integral. The final volume calculated is 135π. The conversation highlights the importance of correctly setting up the bounds for the integral in triple integrals.
iamalexalright
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Homework Statement


Been awhile since I've done them and my memory/reasoning isn't so great apparently...

Use the triple integral to find the volume of the given solid:
The solid enclosed by the cylinder
x^{2} + y^{2} = 9
and the planes y + z = 16 and z = 1. 2. The attempt at a solution
Difficulty is always setting up the bounds of the integral...
-3 \leq y \leq 3
1 \leq z \leq 16 - y
having problems with the xwould it be:
-\sqrt{9 - y^{2}} \leq x \leq \sqrt{9 - y^{2}} ?
 
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Sure. The planes don't intersect inside the cylinder. So you can parametrize the integral over the x,y in the circle defining the cylinder without worrying about the z value. If the planes had intersected inside the circle they would have had to give you a more elaborate description of the region.
 
135*pi, cool! Thanks Dick
 
iamalexalright said:
135*pi, cool! Thanks Dick

That's what I get. :)
 
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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