Please help me!!! Geometry question.
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Answer:
The volume of the figure is [tex](\frac{l^{3}}{3})[\frac{\pi }{2}-1]\ units^{3}[/tex]
Step-by-step explanation:
we know that
The volume of the figure is equal to the volume of the cone minus the volume of the square pyramid
step 1
Find the volume of the cone
The volume of the cone is equal to
[tex]V=\frac{1}{3}\pi r^{2}h[/tex]
we have
[tex]r=\frac{l\sqrt{2}}{2}\ units[/tex] ----> the diagonal of the square base of pyramid is equal to the diameter of the cone
[tex]h=l\ units[/tex]
substitute
[tex]V=\frac{1}{3}\pi (\frac{l\sqrt{2}}{2})^{2}(l)[/tex]
[tex]V=\frac{1}{6}\pi (l)^{3}\ units^{3}[/tex]
step 2
Find the volume of the square pyramid
The volume of the pyramid is equal to
[tex]V=\frac{1}{3}Bh[/tex]
where
B is the area of the base
h is the height of the pyramid
we have
[tex]h=l\ units[/tex]
[tex]B=l^{2}\ units^{2}[/tex]
substitute
[tex]V=\frac{1}{3}l^{2}(l)[/tex]
[tex]V=\frac{1}{3}l^{3}\ units^{3}[/tex]
step 3
Find the volume of the figure
[tex]\frac{1}{6}\pi (l)^{3}\ units^{3}-\frac{1}{3}l^{3}\ units^{3}=(\frac{l^{3}}{3})[\frac{\pi }{2}-1]\ units^{3}[/tex]