\
Find
at
.
\
The trigonometric function
.
\
.
\
Substitute
in above expression.
\
\
\
The exact value of
at
is
.
![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=e1ebac23510bde6f49ad3b8807997506.png\")
at ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=ae8dc3fec4435446db0cadd616cdf435.png\")
. at .![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=1f504de7854e635b5b6c759382a6b43a.png\")
.![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=a6beef3966be1f2ea5f86364eea458f5.png\")
.![\"\"](\"http://www.mathskey.com/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=ae8dc3fec4435446db0cadd616cdf435.png\")
in above expression.![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=d0efee09e590c1345c3ce51cb5c9da43.png\")
![\"\"](\"http://www.mathskey.com/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=e1ebac23510bde6f49ad3b8807997506.png\")
at is ![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=d19ea8dec317fbe5a411fa4b88fab0db.png\")
.