# Java Math sqrt() Method

The sqrt() method of Java Math class returns the accurately rounded positive square root of the specified double value.

Syntax:

public static double sqrt(double a)

Parameters:

The parameter ‘a’ represents the number whose square root is to be determined.

Return Value:

The sqrt() method returns the positive square root of ‘a’.

• It returns zero with same sign as argument, if the argument is positive or negative zero.
• It returns infinity with the same sign as the argument, if the argument is infinite.
• It returns NaN, if the argument is NaN or less than zero.

Example 1:

```public class JavaMathSqrtExample1 {
public static void main(String[] args) {
double a=4.0;
//returns the square root of a double value
System.out.println("Square root of "+ a +" = "+Math.sqrt(a));
}
}```

Output:

`Square root of 4.0 = 2.0`

Example 2:

```public class JavaMathSqrtExample2 {
public static void main(String[] args) {
double a=Double.NaN;
//returns the squre root of a NaN value
System.out.println("Square root of "+ a +" = "+Math.sqrt(a));
}
}```

Output:

`Square root of NaN = NaN`

Example 3:

```public class JavaMathSqrtExample3 {
public static void main(String[] args) {
double a=-0.0;
//returns a zero with the same sign as the argument ,if the argument is zero.
System.out.println("Square root of "+ a +" = "+Math.sqrt(a));
}
}```

Output:

`Square root of -0.0 = -0.0`

Example 4:

```public class JavaMathSqrtExample4 {
public static void main(String[] args) {
double a=-5/0.0;
//returns NaN,if the argument is less than zero.
System.out.println("Square root of "+ a +" = "+Math.sqrt(a));
}
}```

Output:

`Square root of -Infinity = NaN`

Example 5:

```public class JavaMathSqrtExample5 {
public static void main(String[] args) {
double a=Double.POSITIVE_INFINITY;
//returns Infinity,if the argument is Positive infinity.
System.out.println("Square root of "+ a +" = "+Math.sqrt(a));
}
}```

Output:

`Square root of Infinity = Infinity`