Question 198061
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The mathematical concept of a function expresses dependence between two quantities, one of which is known and the other which is produced. A function associates a single output to each input element drawn from a fixed set, such as the real numbers (*[tex \LARGE \R]), although different inputs may have the same output.


a.  Function.  No value of x will result in more than one value for f(x)


b.  Function.  Same reason.


c.  Not a function.  If x = 0, then f(x) is 7 or -7, violating the restriction of a single output for each input element.



John
*[tex \LARGE e^{i\pi} + 1 = 0]
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