![\"\"](\"/userfiles/image/steps_images/step1.JPG\")
It is important to establish a common reference for measuring the direction of a vector.
\Lack of a common reference results a confusion in deciding the direction of the vector.
\That![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=aab30fd462011f6124ff0d81eb26f565.png\")
s why in general we consider positive ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=8da2268e35b6b6daab9c47f71c4c8bf4.png\")
-axis as common reference.
\
It is important to establish a common reference for measuring the direction of a vector.