Please teach me how to graph a cylinder: .
Since is not in the equation, is unrestricted.
. . The -values are on
The graph extends "up" and "down" infinitely.
When , we have the trace of the cylinder on the -plane
. . . . . the "floor" of the coordinate system.
This trace is: .
This is an ellipse with major axis 6 in the -direction
. . and minor axis 3 in the -direction.
Sketch this ellipse on the -plane (the "floor")
. . then draw the cylinder "straight up" and "straight down".