![\"\"](\"/userfiles/image/steps_images/step1.JPG\")
Definition of a function :
\A function is a special type of relation in which each element of the domain is paired with exactly one element of the range.
\![\"\"](\"/userfiles/image/steps_images/step2.JPG\")
\
The relation in figure is not a function because each element in the domain does not corresponds to exactly one element in the range.
\The domain of the function is ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=10769b27dc517bfa422d412330875774.png\")
.
The range of the function is ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=b5011cb784a410e9adc5ee05c91c9e07.png\")
.
The element![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=919f8f066532213200e41f35a2ed077e.png\")
of the domain is paired with more than one element of the range, i.e, ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=d9285d5a293c4e12028128b0fb74ba46.png\")
and ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=2a06887749c014f55973fb0163eb3e52.png\")
.
Thus, the relation in figure is not a function.
\![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/solution.JPG\")
The relation in figure is not a function.