The function is .

(a)

Graph :

Draw a coordinate palne.

Graph the function .

.

(b)

Graph :

Graph using graphing utility :

.

(c)

Observe the graph :

Since the line touches the curve of at two points, the function is not one-to-one.

The function is not one-to-one.

(a)

Graph of the function .

(b)

Graph of :

(c) 

The function is not one-to-one function.