The Math.Acos() method in C# returns the angle whose cosine is the specified number. This number is a double value argument.
Syntax
The syntax is as follows −
public static double Acos (double val);
Above, Val is the number representing a cosine, where Val must be greater than or equal to -1, but less than or equal to 1.
Example
Let us now see an example to implement Math.Acos() method −
using System;
public class Demo {
public static void Main(){
double val1 = -0.0;
double val2 = Double.PositiveInfinity;
double val3 = Double.NaN;
Console.WriteLine("Return value of {0} : {1}", val1, Math.Acos(val1));
Console.WriteLine("Return value of {0} : {1}", val2, Math.Acos(val2));
Console.WriteLine("Return value of {0} : {1}", val2, Math.Acos(val3));
}
}Output
This will produce the following output −
Return value of 0 : 1.5707963267949 Return value of ∞ : NaN Return value of ∞ : NaN
Example
Let us see another example to implement Math.Acos() method −
using System;
public class Demo {
public static void Main(){
double val1 = -30.0;
double val2 = 30.0;
double val3 = 0;
Console.WriteLine("Return value of {0} : {1}", val1, Math.Acos(val1)); Console.WriteLine("Return value of {0} : {1}", val2, Math.Acos(val2));
Console.WriteLine("Return value of {0} : {1}", val2, Math.Acos(val3));
}
}Output
This will produce the following output −
Return value of -30 : NaN Return value of 30 : NaN Return value of 30 : 1.5707963267949