If ,then .
Hypothesis: If
The hypothesis is true.
Conclusion: then .
The conclusion is true.
The modules is represent sign either positive or negative,then .
The statement is true.
![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/step1.JPG\")
![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=3759613b0a736c12cf4b6b605c3a5dc8.png\")
,then ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=6a3ae4cc6750a9d5e016415ed03c84b6.png\")
..![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=d0d1fc175dad14a2001c5e74eb006f63.png\")
.![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/solution.JPG\")
![\"\"](\"http://www.mathskey.com/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=6a3ae4cc6750a9d5e016415ed03c84b6.png\")
is true.