dfresenius Group Title Using integrals, how do you find the volume of a equilateral triangle based pyramid with height h? let a equal one side of the triangular base one year ago one year ago

1. slaaibak Group Title

Ha, good question. Hmm, I think it would be best to define a pyramid in terms of planes, and then using rectangular coordinates to solve

2. dfresenius Group Title

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3. dfresenius Group Title

@Algebraic! hey Chief, can you help me out with this volume problem?

4. dfresenius Group Title

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5. slaaibak Group Title
6. dfresenius Group Title

How does he get A=root(3)/2 (a^2)

7. slaaibak Group Title

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8. slaaibak Group Title

That's using pythagoras. Then the area is just A=bh/2

9. slaaibak Group Title

hmm weird, i'd get A=root(3)/4 (a^2)

10. dfresenius Group Title

Huh. That is weird. That's what I got also.

11. slaaibak Group Title

he made a mistake it seems. $A = {\sqrt 3 \over 4} \times a^2$

12. dfresenius Group Title

Would that mean this his equation for S(r) is wrong also?

13. slaaibak Group Title

I think S(r) is correct.