 # Java Math tan()

The Java Math tan() method returns the trigonometric tangent of the specified angle.

The syntax of the `tan()` method is:

``Math.tan(double angle)``

Here, `tan()` is a static method. Hence, we are accessing the method using the class name, `Math`.

## tan() Parameters

The `tan()` method takes a single parameter.

• angle - angle whose trigonometric tangent is to be returned

Note: The value of the angle is in radians.

## tan() Return Value

• returns the trigonometric tangent of the specified angle
• returns NaN if the specified angle is NaN or infinity

Note: If the argument is zero, then the result of the `tan()` method is also zero with the same sign as the argument.

## Example 1: Java Math tan()

``````import java.lang.Math;

class Main {
public static void main(String[] args) {

// create variable in Degree
double a = 30;
double b = 45;

// get the trigonometric tangent value
System.out.println(Math.tan(a));   // 0.49999999999999994
System.out.println(Math.tan(b));   // 0.7071067811865475

// tan() with 0 as its argument
System.out.println(Math.tan(0.0));  // 0.0
}
}``````

In the above example, we have imported the `java.lang.Math` package. This is important if we want to use methods of the `Math` class. Notice the expression,

``Math.tan(a)``

Here, we have directly used the class name to call the method. It is because `tan()` is a static method.

Note: We have used the Java Math.toRadians() method to convert all the values into radians. It is because as per the official Java documentation, the `tan()` method takes the parameter as radians.

## Example 2: Math tan() Returns NaN

``````import java.lang.Math;

class Main {
public static void main(String[] args) {

// create variable
// square root of negative number
// results in not a number (NaN)
double a = Math.sqrt(-5);

// Using Double to implement infinity
double infinity = Double.POSITIVE_INFINITY;

// print the tangent  value
System.out.println(Math.tan(a));  // NaN
System.out.println(Math.tan(infinity));  // NaN
}
}``````

Here, we have created a variable named a.

• Math.tan(a) - returns NaN because square root of a negative number (-5) is not a number

The `Double.POSITIVE_INFINITY` is a field of `Double` class. It is used to implement infinity in Java.

Note: We have used the Java Math.sqrt() method to compute the square root of a number.