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Find an equation for a 3D object and plot it

mark

(10 pts)

For this problem, you’re going to find an equation describing a simple 3D object like a sphere or cylinder. You should then respond to this post by

Telling us your assigned 3D object,
Typing out your equation in LaTeX format, and
Including a 3D graph of your object.

You’re welcome to try any 3D graphing software that you know. I recommend that most folks try Calc Plot 3D, which has a simple, Desmos like interface for 3D graphs.

To get your problem, choose your name from the following list:

mark

audrey

My 3D object is the cylinder of radius 2 whose axis goes through the point (2,-2,-2) and is parallel to the $y$ -axis. An equation for that cylinder is

$(x-2)^2 + (z+2)^2 = 4.$

Screenshot 2023-01-11 091508

whardin3

My 3D object is a sphere with a radius of 5 centered at (-2, 1, -4).
The equation I used was:

$(x+2)^2+(y-1)^2+(z+4)^2=25$

My 3D Graph is:

dfleming

My 3D object was the sphere of radius 5 centered at the point (1,-1,-4).
The equation I used was:

$(x-1)^2 + (y+1)^2 + (z+4)^2 = 25$

My 3D graph is:

chughes2

My assigned object was a cylinder with a radius of 5 whos axis goes through the point (0,1,-4) and is parallel to the x-axis.

The equation I created was $(y-1)^2+(z+4)^2=25$ . So I could put the equation into the graphing calculator given, I put the equation into the form $z=\sqrt{-(y-1)^2+25}-4$ , and gave it the negative counterpart $z=-\sqrt{-(y-1)^2+25}-4$ to give the full cylinder for the visual.