The Delta FunctionDefinition: The {$\Delta$} function acts on unordered triples of numbers by subtracting the two smaller numbers from the largest number. For the {$a\times b\times c$} box {$T$}, with {$a\le b\le c$}, {$\Delta (T)$} is the {$a\times b\times (c-a-b)$} box. |