7. Sketch the cylindrical surface r = (1/2) + cos(
q
),0
£
q
£
2
p
,
0
£
z
£
1.
Solution
: begin with the polar graph of r = (1/2) + cos(
q
) in the x-y plane:
Then, to incorporate the 0
£
z
£
1 condition, add the perpendiculars to the curve: