# JavaScript | Math.tanh() function

Math.tanh() is an inbuilt function in JavaScript which is used to calculate the value of hyperbolic tangent of a number.
Syntax:

`Math.tanh(p)`

Parameter:

• Here the parameter p is a number for which the value of hyperbolic tangent is going to be calculated.
• Return value:

• It returns the calculated value of the hyperbolic tangent of the number.
• Examples:

```Input:
Math.tanh(0)
Output:
0```

Explanation:
Here formula for calculating hyperbolic tangent of any number is : The number e is a mathematical constant having an approximate value equal to 2.718. In the same way hyperbolic tangent of any number can be calculated just after replacing p with the desired number.

```Input:
Math.tanh(18)
Output:
0.9999999999999996```

Explanation:
Here same as above calculation, when we put 18 instead of p then the value becomes as output shown above.
Let’s see some JavaScript code:

 `// Printing hyperbolic tangent of some numbers ` `// taken as paramter of Math.tanh() function. ` `console.log(Math.tanh(0)); ` `console.log(Math.tanh(1)); ` `console.log(Math.tanh(5)); ` `console.log(Math.tanh(22)); ` `console.log(Math.tanh(-2)); ` `console.log(Math.tanh(4)); `

/div>

Output:

```> 0
> 0.7615941559557649
> 0.9999092042625951
> 1
> -0.9640275800758169
> 0.999329299739067```

Errors and Exceptions:
1. It is an error case because complex number can not be taken as the parameter of the function only integer value can be taken as the parameter.

 `// complex number can not be calculated as the hyperbolic tangent. ` `console.log(Math.tanh(1 + 2i)); `

Output:

`Error: Invalid or unexpected token`

2. Other than integer nothing is accepted as the parameter of the function that is why here string as the parameter gives NaN i.e, not a number.

 `// Any string value as the parameter of the function ` `// gives NaN i.e, not a number ` `// because only number can be used as the parameters. ` `console.log(Math.tanh(``"geeksforgeeks"``)); ` `console.log(Math.tanh(``"gfg"``)); `

Output:

```> NaN
> NaN```

Application:

• Its practical application is that whenever we need to find the value of the hyperbolic tangent of a number that time we take the help of Math.tanh() function in JavaScript.
•  `// Printing hyperbolic tangent of some numbers from 0 to 9 ` `// taken as paramter of Math.tanh() function. ` `for` `(i = 0; i < 10; i++) { ` `    ``console.log(Math.tanh(i)); ` `    ``+``"
"``; ` `} `

Output:

```> 0
> 0.7615941559557649
> 0.9640275800758169
> 0.9950547536867305
> 0.999329299739067
> 0.9999092042625951
> 0.9999877116507956
> 0.9999983369439447
> 0.9999997749296758
> 0.999999969540041```