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Active Calculus - Multivariable

Activity 12.8.6.
Consider the solid \(S'\) defined by the inequalities \(0 \leq x \leq 2\text{,}\) \(\frac{x}{2} \leq y \leq \frac{x}{2}+1\text{,}\) and \(0 \leq z \leq 6\text{.}\) Consider the transformation defined by \(s = \frac{x}{2}\text{,}\) \(t = \frac{x-2y}{2}\text{,}\) and \(u = \frac{z}{3}\text{.}\) Let \(f(x,y,x) = x-2y+z\text{.}\)
(a)
The transformation turns the solid \(S'\) in \(xyz\)-coordinates into a box \(S\) in \(stu\)-coordinates. Apply the transformation to the boundries of the solid \(S'\) to find \(stu\)-coordinate descriptions of the box \(S\text{.}\)
(b)
Compute and simplify the Jacobian \(\frac{\partial(x,y,z)}{\partial(s,t,u)}\text{.}\)
(c)
Use the transformation to perform a change of variables and evaluate \(\iiint_{S'} f(x,y,z) \, dV\) by evaluating
\begin{equation*} \iiint_{S} f(x(s,t,u),y(s,t,u),z(s,t,u)) \ \left| \frac{\partial(x,y,z)}{\partial(s,t,u)} \right| \, ds \, dt \, du \end{equation*}