Getting the acos, asin or atan or a number

The asin is the inverse sin: sin(a) = b, asin(b) = a
The acos is the inverse cos: cos(a) = b, acos(b) = a
The atan is the inverse tan: tan(a) = b, atan(b) = a

To use asin, acos and atan in your Java programs, use the static methods in the Math class.
Here’s an example:

import java.math.*;
                           
public class Main 
{  
   public static void main(String args[]) throws Exception {
      double asinAngle = Math.asin(0.6287930240184686);
      double acosAngle = Math.acos(0.7775727187509279);
      double atanAngle = Math.atan(0.8086613751425653);
 
      System.out.println("asin: " + asinAngle);
      System.out.println("acos: " + acosAngle);
      System.out.println("atan: " + atanAngle);
   }
}

outputs:

asin: 0.6800000000000002
acos: 0.68
atan: 0.68

Note: angles to the trigonometric math methods should be given in radians.
If you want to use degrees, you have to convert the radians first:

     360 degrees = 2 pi radians
 
     So, to convert radians into degrees, multiply by 180 / Math.PI
         to convert degrees into radians, multiply by Math.PI / 180