note 79607 added to function.acos

To calculate an angle from a triangle's sides. Use the 'law of cosines' : <?php // a²+b²-c² // cosC = -------- // 2ab function calculateAngle($c,$a,$b) { $angleInRadians=acos((pow($a,2) + pow($b,2) - pow($c,2)) / (2 * $a * $b)); return rad2deg($angleInRadians); } ?> $a, $b, $c are the triangle sides. The function returns the angle opposite side c, in degrees. ---- Server IP: 87.124.64.96 Probable Submitter: 80.229.147.209 ---- Manual Page -- http://www.php.net/manual/en/function.acos.php Edit -- https://master.php.net/note/edit/79607 Del: integrated -- https://master.php.net/note/delete/79607/integrated Del: useless -- https://master.php.net/note/delete/79607/useless Del: bad code -- https://master.php.net/note/delete/79607/bad+code Del: spam -- https://master.php.net/note/delete/79607/spam Del: non-english -- https://master.php.net/note/delete/79607/non-english Del: in docs -- https://master.php.net/note/delete/79607/in+docs Del: other reasons-- https://master.php.net/note/delete/79607 Reject -- https://master.php.net/note/reject/79607 Search -- https://master.php.net/manage/user-notes.php