-->

Motion In A Plane

Question
CBSEENPH11018355

Find the area of parallelogram formed by space straight A with rightwards arrow on top space equals space straight i with hat on top minus straight j with hat on top plus 2 straight k with hat on top  and <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)
#1 /home/config_admin/public/felixventures.in/public/application/css/plugins/tiny_mce_wiris/integration/lib/com/wiris/util/sys/Store.class.php(56): mkdir('/home/config_ad...', 493)
#2 /home/config_admin/public/felixventures.in/public/application/css/plugins/tiny_mce_wiris/integration/lib/com/wiris/plugin/impl/FolderTreeStorageAndCache.class.php(110): com_wiris_util_sys_Store->mkdirs()
#3 /home/config_admin/public/felixventures.in/public/application/css/plugins/tiny_mce_wiris/integration/lib/com/wiris/plugin/impl/RenderImpl.class.php(231): com_wiris_plugin_impl_FolderTreeStorageAndCache->codeDigest('mml=<math xmlns...')
#4 /home/config_admin/public/felixventures.in/public/application/css/plugins/tiny_mce_wiris/integration/lib/com/wiris/plugin/impl/TextServiceImpl.class.php(59): com_wiris_plugin_impl_RenderImpl->computeDigest(NULL, Array)
#5 /home/config_admin/public/felixventures.in/public/application/css/plugins/tiny_mce_wiris/integration/service.php(19): com_wiris_plugin_impl_TextServiceImpl->service('mathml2accessib...', Array)
#6 {main}</pre>.

Solution

Given,
Here,  straight A with rightwards arrow on top equals straight i with hat on top minus straight j with hat on top plus 2 straight k with hat on top,    straight B with rightwards arrow on top space equals space minus 3 straight i with hat on top plus 4 straight j with hat on top minus straight k with hat on top
∴    space space space space space space space space space space space space space space space space space space space space space space space space space space straight i with hat on top space space space space space space space space space space space space stack straight j space with hat on top space space space space space space space space space space space space space straight k with hat on top
straight A with rightwards arrow on top cross times straight B with rightwards arrow on top space equals space space space space space space space space space space 1 space space space space space space space minus 1 space space space space space space space space space space space space 2
space space space space space space space space space space space space space space space space space space space space space space space minus 3 space space space space space space space space 4 space space space space space space space space space space minus 1 
            space space equals left square bracket left parenthesis negative 1 right parenthesis left parenthesis negative 1 right parenthesis minus left parenthesis 2 right parenthesis left parenthesis 4 right parenthesis right square bracket straight i with hat on top minus left square bracket left parenthesis 1 right parenthesis left parenthesis negative 1 right parenthesis minus left parenthesis 2 right parenthesis left parenthesis negative 3 right parenthesis right square bracket straight j with hat on top                                          plus left square bracket left parenthesis 1 right parenthesis left parenthesis 4 right parenthesis space minus space left parenthesis negative 1 right parenthesis left parenthesis negative 3 right parenthesis right square bracket straight k with hat on top

              equals negative 7 straight i with hat on top minus 5 straight j with hat on top plus straight k with hat on top
 Now the area of parallelogram formed by vectors straight A with rightwards arrow on top space and space straight B with rightwards arrow on top is, 
   open vertical bar straight A with rightwards arrow on top cross times straight B with rightwards arrow on top close vertical bar space equals space square root of left parenthesis negative 7 right parenthesis squared plus left parenthesis negative 5 right parenthesis squared plus left parenthesis 1 right parenthesis squared end root space equals space square root of 75 space equals space 5 square root of 3