in 1888 in Calcolo geometrico secondo l'Ausdehnungslehre di H. Grassmann. Peano also created the large symbols for general intersection and union of more than two classes in his 1908 book Formulario mathematico. See also Constructive solid geometry, Boolean Intersection is one of the ways of combining 2D/3D shapes Dimensionally Extended 9-Intersection Model Meet (lattice theory) Intersection (set theory) Union (set theory) References External links zh-yue:交點 Broad-concept articles