Calculations in a disphenoid. A disphenoid is a tetrahedron with four congruent triangles as faces. Its opposite edges have the same length. Enter the three lengths a, b and c and choose the number of decimal places. Then click Calculate. The squares of any two side lengths must be larger than the square of the third side length (e.g. a=4, b=5, c=6).
Perimeter of one triangle p = a + b + c
A = 4 * √u/2 * (u/2-a) * (u/2-b) * (u/2-c)
V = √ (a² + b² - c²) * (a² - b² + c²) * (-a² + b² + c²) / 72
rc = √ (a² + b² + c²) / 8
ri = 3 * V / A
Lengths and radiuses have the same unit (e.g. meter), the area has this unit squared (e.g. square meter), the volume has this unit to the power of three (e.g. cubic meter). A/V has this unit -1.