Math Trigonometric functions SIN() to get Sin value of any radian as input in PHP

Calculate the sine of an angle

sin() expects the angle in radians. Convert degree input with deg2rad() first.

$angle = deg2rad(30);
echo sin($angle); // approximately 0.5

Start with this current pattern. The examples below are retained for additional variations, output and reference.

SIN(X);

X is the angular value in radian. We get output as Sin of the input angle.

<?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()

We can use deg2rad() to convert Degree value to radian and then use 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

These examples expand on how to use the `sin()` function in common scenarios, such as calculating angles and dealing with large values.

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

Math Functions SIN() function rad2deg() function

Subhendu Mohapatra

Author & Instructor at plus2net

I write and maintain practical tutorials on Python, PHP, SQL, JavaScript, HTML, jQuery, and web development at plus2net. The tutorials focus on clear explanations, working examples, and code that readers can test and adapt while learning.

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