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In solid geometry, if the volume of a triangular pyramid with equal edge length is 2 / 3 of its root sign, the surface area of the pyramid is
This is a regular tetrahedron
Let the edge length be a, then the volume is SQR (2) a ^ 3 / 12
SQR (2) a ^ 3 / 12 = 2sqr (2) / 3 leads to a = 2
The surface area is SQR (3) a ^ 2 = 4sqr (3)
Note: SQR (x) denotes root X
A ^ 3 and a ^ 2 represent the cube and square of a respectively
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