MHB 15.4.20 volumn via triple integrals

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The discussion focuses on calculating the volume of a region in the first octant bounded by the coordinate planes and the surface defined by the equation z=4-x^2-y. The constraints for the triple integral are established as 0 ≤ z ≤ 4-x^2-y, 0 ≤ y ≤ 4-x^2, and 0 ≤ x ≤ z. The volume is computed using the triple integral V = ∫∫∫ dz dy dx, with specific limits for each variable. Participants are encouraged to explore the integral in different orders, specifically dydzdx and dydxdz. The conversation emphasizes verifying the correctness of the approach taken in the calculations.
karush
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$\textsf{The region in the first octant bounded by the coordinate planes and the surface }$
View attachment 8112
$$z=4-x^2-y$$
$\textit{From the given equation we get}$
\begin{align*}\displaystyle
&0 \le z \le 4-x^2-y\\
&0 \le y \le 4-x^2\\
&0 \le x \le z
\end{align*}
$\textit{Thus the triple Integral results:}$
\begin{align*}\displaystyle
V&=\iiint\limits_{E} \, dzdyd
\quad =\int_{0}^{2}
\int_{0}^{4-x^2}
\int_{0}^{4-x^2-y}
\, dzdydx
\end{align*}
So just seeing if this is going the right direction
$\tiny{15.4.20}$
 
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karush said:
$\textsf{The region in the first octant bounded by the coordinate planes and the surface }$

$$z=4-x^2-y$$
$\textit{From the given equation we get}$
\begin{align*}\displaystyle
&0 \le z \le 4-x^2-y\\
&0 \le y \le 4-x^2\\
&0 \le x \le z
\end{align*}
$\textit{Thus the triple Integral results:}$
\begin{align*}\displaystyle
V&=\iiint\limits_{E} \, dzdyd
\quad =\int_{0}^{2}
\int_{0}^{4-x^2}
\int_{0}^{4-x^2-y}
\, dzdydx
\end{align*}
So just seeing if this is going the right direction
$\tiny{15.4.20}$

It's a good thing you didn't need that equation on the upper left.

Okay, now do it all over dydzdx and dydxdz.