If the coordinates of points P and Q are (3, 1, -2) and (1, -2, 2) respectively, then find the vector 
The vector PQ is [(3-1)
+ (1-(-2)
+ (-2-2)
So,
What is the component of vector ![<pre>uncaught exception: <b>mkdir(): Permission denied (errno: 2) in /home/config_admin/public/felixventures.in/public/application/css/plugins/tiny_mce_wiris/integration/lib/com/wiris/util/sys/Store.class.php at line #56mkdir(): Permission denied</b><br /><br />in file: /home/config_admin/public/felixventures.in/public/application/css/plugins/tiny_mce_wiris/integration/lib/com/wiris/util/sys/Store.class.php line 56<br />#0 [internal function]: _hx_error_handler(2, 'mkdir(): Permis...', '/home/config_ad...', 56, Array)
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perpendicular to XY plane?
The component of vector is perpendicular in the XY plane in the Z direction.
So, it is 
Switch
is null vector?
