## Denebel Group Title A solid has a circular base of radius 3. If every plane cross section perpendicular to the x- axis is an equilateral triangle, the. It's volume is.. 2 years ago 2 years ago

1. experimentX

??? couldn't picture at all

2. Denebel

*then, it's volume is ...

3. TuringTest

|dw:1334049066451:dw|imagine a bunch of triangles popping out in the z-direction

4. dumbcow

circle: x^2 + y^2 = 9 --> y = sqrt(9-x^2) |dw:1334048930933:dw| volume is sum of all the areas of the triangles area = sqrt3/4 *(2y)^2 = sqrt3 y^2 = sqrt3(9-x^2) $V = \sqrt{3}\int\limits_{-3}^{3}(9-x^{2}) dx$

5. TuringTest

^what dumbcow said|dw:1334049136750:dw|

6. Denebel

Oh I see! Thanks.