A treatise on special or elementary geometry (1877)
Olney, Edward, 1827-1887, Olney, Edward, 1827-1887. Elements of trigonometry, plane and spherical · New York : Sheldon · leaf 225
of its progressthe sections are equivalent, and as theplane reaches both vertices at thesame time, by reason of the common altitude, it is evident that the volumes areequal. Or, if desired, we may consider the two pyramids as divided into an equalnumber of infinitely thin lam^.ncB parallel to the… … OP PYRAMIDS AND CONES, 205 PROPOSITION VI. 520. Uieorem.—TJie volume of a triangular pyramid is equalto one-third the product of its base and altitude. Dem.—Let S-ABC be a triangular pyramid,whose altitude is H*; then is the volume equalto ^ H X area ABC. For, throui^h A and B draw Aa and Bh…
Geometry · Trigonometry
Internet Archive · California Digital Library · Public Domain Mark 1.0. Free to use for anything.
