PHP tanh( ) Function

The tanh() function is a builtin function in PHP and is used to find the hyperbolic tangent of an angle passed to it as parameter.
The hyperbolic tangent of any argument arg is defined as,

sinh(arg) / cosh(arg)

Where, sinh() is the hyperbolic sine function and cosh() is the hyperbolic cosine function.

Syntax:

float tanh($value)

Parameters: This function accepts a single parameter $value. It is the number whose hyperbolic tangent value you want to find. The value of this parameter must be in radians.

Return Value: It returns a floating point number which is the hyperbolic tangent value of a number passed to it as argument.

Examples:

Input : tanh(0.50)  
Output : 0.46211715726001

Input : tanh(-0.50) 
Output : -0.46211715726001

Input : tanh(5)
Output : 0.9999092042626

Input : tanh(M_PI_4) 
Output : 0.65579420263267

Below programs, taking different values of $value are used to illustrate the tanh() function in PHP:

• Passing 0.50 as a parameter:

  <?php
  
  echo (tanh(0.50));
  
  ?>

  Output:

  0.46211715726001

• Passing -0.50 as a parameter:

  <?php
  
  echo (tanh(-0.50));
  
  ?>

  Output:

  -0.46211715726001

• Passing 5 as a parameter:

  <?php
  
  echo (tanh(5));
  
  ?>

  Output:

  0.9999092042626

• When (M_PI_4) is passed as a parameter, M_PI is a constant in PHP whose value is 0.78539816339744830962 :

  <?php
  
  echo (tanh(M_PI_4));
  
  ?>

  Output:

  0.65579420263267

Reference:
http://php.net/manual/en/function.tanh.php