SIN(): sine of a specified angle given in Radians

SIN(X);

<?Php
echo SIN(PI()); // Output is 1.2246467991474E-16  // same as 0 
echo "<br>";
echo SIN(PI()/2); // Output  1 
echo "<br>";
echo SIN(PI()/3); // Output is 0.86602540378444
echo "<br>";
echo SIN(PI()/4); // Output is 0.70710678118655 
?>

deg2rad() with SIN()

<?Php
echo SIN(deg2rad(0)); // Output  is 0
echo "<br>";
echo SIN(deg2rad(90)); // Output is 1
echo "<br>";
echo SIN(deg2rad(180)); // Output  is 1.2246467991474E-16 // same as 0 
?>

Example: Sine of Negative Angles

$angle = -30;
echo sin(deg2rad($angle));  // Output: -0.5

Example: Using Sin in Waveform Calculations

$frequency = 50;
$time = 0.02;
echo sin(2 * M_PI * $frequency * $time);  // Output: waveform at specific time

Example: Sine of 45 Degrees

$angle = 45;
echo sin(deg2rad($angle));  // Output: 0.70710678118655

Example: Sine of Large Angles

$angle = 720;  // Angle greater than 360 degrees
echo sin(deg2rad($angle));  // Output: 0 (Since sin(720) = sin(0))

Example: Sine in a Triangle

$hypotenuse = 10;
$opposite = 5;
$angle = rad2deg(asin($opposite / $hypotenuse));
echo $angle;  // Output: 30 degrees

Plotting of SIN & SIN curves by using PHP GD function with deg2rad()

Subhendu Mohapatra

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