Assignment 7

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course Mth 277

6/22 11 pm

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Question: Identify the quadric surface 4y = (z^2)/4 - (x^2)/9.

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Your solution:

This surface is a hyperbolic parabaloid, since the two signs are different and one of the variables is of order 1.

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Self-critique (if necessary):

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Question: Identify the quadric surface given by the equation 8z^2 = (1/8) + (x^2)/9 + (y^2). Describe the traces in planes parallel to the coordinate planes (and sketch the graph).

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Your solution:

This quadric surface is a one sheet hyperboloid.

The intersection of the hyperboloid with planes parallel to the two primary planes form ellipses with varying axes.

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Given Solution:

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Self-critique (if necessary):

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Question: Describe the quadric surface given by the equation ((x-3)^2)/2 - ((y-1)^2)/4 - (z^2-2)/9 = 4.

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Your solution:

This surface is a two sheet hyperboloid, with vertices at (3,1,5) and (3,1,-1).

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Self-critique (if necessary):

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Question: Describe the curve intersection of the two quadric surfaces 4z = (y^2)/9 - (x^2)/16 and (x^2)/4 + 2(y^2) - 4(z^2)/3 = 1.

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Your solution:

4z = (y^2)/9 - (x^2)/16 describes a hyperbolic paraboloid centered around the origin.

x^2/4 + 2y^2/2 - 4z^2/3 = 1 describes a one-sheet hyperboloid centered around the origin.

A slice of the first graph would give us an ellipse, and a slice of the second would give as a parabola.

Therefore, it makes sense that an intersection of the two would yield a elliptic paraboloid.

confidence rating #$&*:

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Given Solution:

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Self-critique (if necessary):

Most of this was touch and go, it's a little difficult to visualize the 3D objects in my head.

I tried drawing out each pair of axes (XZ, YZ, XY) and combining them, and that was helpful when determining what kinds of quadric surface each was.

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Self-critique rating:"

&#Your work looks good. Let me know if you have any questions. &#