ACT OF UNION BETWEEN THE EASTERN AND WESTERN CHEROKEES. WHEREAS, our fathers have existed as a separate and distinct Nation, in the possession and exercise of the essential and appropriate attributes of sovereignty, from a period extending into antiquity, beyond the records and memory of man; and
A surjective function f from the real numbers to the real numbers possesses an inverse as long as it is one-to-one, i.e. as long as the graph of y = f(x) has, for each possible y value only one corresponding x value, and thus passes the horizontal line test.
In mathematics, a function is a relation between a set of inputs and a set of permissible outputs with the property that each input is related to exactly one output. An example is the function that relates each real number x to its square x 2.