PHP is a popular programming language that is widely used for web development.

One of the key features of PHP is its built-in support for mathematical operations.

We will take a look at some of the most commonly used mathematical functions in PHP and provide examples of how to use them.

## Basic Mathematical Operations

PHP provides several basic mathematical operations that can be used for performing calculations.

These include addition +, subtraction -, multiplication *, and division /.

These operations can be used to perform calculations on both integers and floating-point numbers.

For example, the following code calculates the sum of two numbers:

```
$num1 = 5;
$num2 = 10;
$sum = $num1 + $num2;
echo $sum; // Outputs 15
```

Similarly, the following code calculates the product of two numbers:

```
$num1 = 5;
$num2 = 10;
$product = $num1 * $num2;
echo $product; // Outputs 50
```

## Modulus Operator

The modulus operator % returns the remainder of a division operation.

For example, the following code calculates the remainder of a division operation:

```
$num1 = 5;
$num2 = 3;
$remainder = $num1 % $num2;
echo $remainder; // Outputs 2
```

## PI Function

The pi() function returns the value of PI:

Example:

`echo(pi()); // returns 3.1415926535898`

## Exponentiation

PHP provides a built-in function for performing exponentiation. The function is called pow() and takes two arguments: the base number and the exponent.

For example, the following code calculates the value of 2 raised to the power of 3:

```
$base = 2;
$exponent = 3;
$result = pow($base, $exponent);
echo $result; // Outputs 8
```

## Square Root

The square root of a number can be calculated using the sqrt() function. This function takes a single argument, which is the number for which the square root is to be calculated.

For example, the following code calculates the square root of 25:

```
$number = 25;
$result = sqrt($number);
echo $result; // Outputs 5
```

## Absolute Value

The absolute value of a number can be calculated using the abs() function. This function takes a single argument, which is the number for which the absolute value is to be calculated.

For example, the following code calculates the absolute value of -5:

```
$number = -5;
$result = abs($number);
echo $result; // Outputs 5
```

## Rounding

PHP provides several built-in functions for rounding numbers. The round() function can be used to round a number to the nearest integer. The ceil() function rounds a number up to the nearest integer, and the floor() function rounds a number down to the nearest integer.

For example, the following code uses the round() function to round the number 3.14 to the nearest integer:

```
$number = 3.14;
$result = round($number);
echo $result; // Outputs 3
```

Similarly, the following code uses the ceil() function to round the number 3.14 up to the nearest integer:

```
$number = 3.14;
$result = ceil($number);
echo $result; // Outputs 4
```

## Random Numbers

PHP also provides several built-in functions for generating random numbers.

The rand() function can be used to generate a random integer within a specified range.

The mt_rand() function is an improved version of rand() and generates a better quality random number.

Both functions take two arguments: the minimum and maximum values of the range.

For example, the following code uses the rand() function to generate a random number between 1 and 100:

```
$min = 1;
$max = 100;
$result = rand($min, $max);
echo $result; // Outputs a random number between 1 and 100
```

Similarly, the following code uses the mt_rand() function to generate a random number between 1 and 100:

```
$min = 1;
$max = 100;
$result = mt_rand($min, $max);
echo $result; // Outputs a random number between 1 and 100
```

## Trigonometric Functions

PHP also provides support for trigonometric functions such as sin(), cos(), and tan(). These functions take an angle in radians as an argument and return the corresponding trigonometric value.

For example, the following code calculates the sine of 30 degrees:

```
$angle = deg2rad(30);
$result = sin($angle);
echo $result; // Outputs 0.5
```

Similarly, the following code calculates the cosine of 60 degrees:

```
$angle = deg2rad(60);
$result = cos($angle);
echo $result; // Outputs 0.5
```

## Takeaways

PHP provides a wide range of built-in mathematical functions that can be used for performing various calculations.

These functions cover basic mathematical operations, modulus, exponentiation, square root, absolute value, rounding, random numbers, and trigonometric functions.

With these functions, it's easy to perform complex mathematical calculations in your PHP scripts.