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dfresenius
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
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
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@Algebraic! hey Chief, can you help me out with this volume problem?
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http://mathhelpforum.com/calculus/107926-find-volume-described-solid.html
How does he get A=root(3)/2 (a^2)
That's using pythagoras. Then the area is just A=bh/2
hmm weird, i'd get A=root(3)/4 (a^2)
Huh. That is weird. That's what I got also.
he made a mistake it seems. \[A = {\sqrt 3 \over 4} \times a^2\]
Would that mean this his equation for S(r) is wrong also?
I think S(r) is correct.