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Active Calculus - Multivariable

Preview Activity 13.10.1.
In this preview activity, we will explore the parameterizations of a few familiar surfaces and confirm some of the geometric properties described in the introduction above.
(a)
Use the ideas from Section 13.9 to give a parameterization \(\vr(s,t)\) of the following surface. Be sure to specify the bounds on each of your parameters.
\(S_1\text{:}\) the right circular cylinder centered on the \(x\)-axis of radius 2 when \(0\leq x\leq 5\)
(b)
Draw a graph of \(S_1\) from the previous part. Label the points that correspond to \((s,t)\) points of \((0,0)\text{,}\) \((0,1)\text{,}\) \((1,0)\text{,}\) and \((2,3)\text{.}\)
(c)
For the parameterization from part a, calculate \(\vr_s\text{,}\) \(\vr_t\text{,}\) and \(\vr_s \times \vr_t\text{.}\)
(d)
For the parameterization from part a, find the value for \(\vr_s\text{,}\)\(\vr_t\text{,}\) and \(\vr_s \times \vr_t\) at the \((s,t)\) points of \((0,0)\text{,}\) \((0,1)\text{,}\) \((1,0)\text{,}\) and \((2,3)\text{.}\)
(e)
Draw your vector results from d on your graph and confirm the geometric properties described in the introduction to this section. Namely, \(\vr_s\) and \(\vr_t\) should be tangent to the surface, while \(\vr_s \times \vr_t\) should be orthogonal to the surface (in addition to \(\vr_s\) and \(\vr_t\)).
(f)
Repeat steps (a) through (e) for the following two surfaces:
(i)
\(S_2\text{:}\) the sphere centered at the origin of radius 3
(ii)
\(S_3\text{:}\) the first octant portion of the plane \(x+2y+3z=6\)