Performing Trigonometry in Javascript

javascript, trigonometry

Solution

var x = Math.atan(450/120);

Gives the answer 75 degrees in radians, which is: 1.3101939350475555

To get the correct answer just convert to degrees:

var x = Math.atan(450/120) * (180/Math.PI);
alert(x); // says x is 75.06858282186245

Problem

How do I perform the following math problem in Javascript: ``` Tan(x) = 450/120; x = 75; // In my calculator I use tan^-1(450/120) to find the answer // How do I perform tan^-1 in javascript??? ``` My javascript code is outputting incorrect results: ``` var x = Math.atan(450/120); alert(x); // says x = 1.3101939350475555 // Maybe I am meant to do any of the following... var x = Math.atan(450/120) * (Math.PI/2); // still wrong answer var x = Math.tan(450/120); // still wrong answer ```

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