PHP sin()

PHP sin(x) function returns the sine value of radian angle x. The principle values for x is [-∞,∞].

<?PHP
	echo sin(M_PI); //1.2246467991474E-16
	echo sin(M_PI/2);  //1
?>

deg2rad() function can be used to convert degree to radian angle.

<?PHP
	echo sin(deg2rad(60));  //0.86602540378444
	echo sin(deg2rad(30));  //0.5
?>

Sine y=sin(x) Graph