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javascriptmathdegreesradians

Math.sin incorrect results even when converted to degrees

I'm trying to use sin on a variable and I saw you can convert it by using / (Math.PI / 180) but that seems contradictory if you want to convert it to degrees.. How do I properly convert and use sin in degree form? (On an iPhone calculator, for example it returns ~.707 from an input of 45, while this returns ~.806).

function click25() {
    if (vi === 0) {
        reactant = Math.sin(reactant / (Math.PI / 180))
    }
}
Solution

  • You need to multiply the value in degree by (pi/180) to convert into the equivalent value in radians

    var reactant = 45;
var vi = 0;
function click25() {
    if (vi === 0) {
        reactant = Math.sin(reactant * (Math.PI / 180))
    }
    console.log(reactant);
}

click25();