A cone has a volume of $12288\pi$ cubic inches and the vertex angle of the vertical cross section is 60 degrees. what is the height of the cone? express your answer as a decimal to the nearest tenth.

Respuesta :

Answer:

The height of the cone is [tex]48\ in[/tex]

Step-by-step explanation:

step 1

Find the radius of the base of cone

we know that

The volume of the cone is equal to

[tex]V=\frac{1}{3}\pi r^{2} h[/tex]

we have

[tex]V=12,288\pi\ in^{3}[/tex]

[tex]tan(30\°)=\frac{r}{h}[/tex]  ---> remember that the vertex angle of the vertical cross section is 60 degrees

so

[tex]r=(h)tan(30\°)[/tex]

[tex]r=(h)\frac{\sqrt{3}}{3}[/tex]

substitute the values and solve for h

[tex]12,288\pi=\frac{1}{3}\pi ((h)\frac{\sqrt{3}}{3})^{2} h[/tex]

[tex]36,864=\frac{h^{3}}{3}[/tex]

[tex]h^{3}=110,592[/tex]

[tex]h=48\ in[/tex]

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