Assertion: function's element | /r/HasProperty | input
Facets:
Source sentences:
text: If the function is called f, this relation is denoted y = f (x) (which is spoken aloud as f of x), the element x is the argument or input of the function, and y is the value of the function, the output, or the image of x by f.
text: Two other reasons, also sufficient by themselves, is that neither 3 nor 4 are first elements (input) of any ordered pair therein.