Volume of a triangle type shape with a square bottom

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SUMMARY

The volume of a solid with a square base in the xy-plane, defined by \(0 \leq x, y \leq 1\) and extending vertically from \(0 \leq z \leq 2\), is calculated to be \(\frac{5}{4}\). The lower section is a cube with a volume of 1, while the upper section consists of triangular cross-sections with bases of 1 unit and heights varying linearly from 0 to 1. The volume of the triangular section is derived using the formula \(dV = \frac{1}{2} x \, dx\), leading to the integral \(\frac{1}{2} \int_0^1 x \, dx\) for the total volume calculation.

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Dustinsfl
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How do I find the volume of this shape? The bottom is a square in the xy plane where \(0\leq x,y\leq 1\).

The object isn't a prism or pyramid so I am not sure what to do.

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If I am interpreting this correctly, for $0\le z\le1$ you have a cube whose sieds are 1 unit in length, and for $1\le z\le2$ you have a solid whose cross-sections perpendicular to either the $x$ or $y$ axes are right triangles whose bases are 1 unit in length and altitudes vary linearly from 0 to 1, and so the volume by slicing is:

$$V=1+\frac{1}{2}\int_0^1 x\,dx=\frac{5}{4}$$
 
MarkFL said:
If I am interpreting this correctly, for $0\le z\le1$ you have a cube whose sieds are 1 unit in length, and for $1\le z\le2$ you have a solid whose cross-sections perpendicular to either the $x$ or $y$ axes are right triangles whose bases are 1 unit in length and altitudes vary linearly from 0 to 1, and so the volume by slicing is:

$$V=1+\frac{1}{2}\int_0^1 x\,dx=\frac{5}{4}$$

How did you derive this formula? Is the 1 the volume of the cube or is that part of the triangular shape?
 
Yes the 1 is the volume of the cubical portion of the solid, and for the upper part, the volume of a particular slice is:

$$dV=\frac{1}{2}bh\,dx$$

where the base is a constant 1 and the height is $x$, hence:

$$dV=\frac{1}{2}x\,dx$$

and so summing the slices (and adding in the cubical portion), we find:

$$V=1+\frac{1}{2}\int_0^1 x\,dx$$
 

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