How to calculate rotation in 2D in Javascript

Question

I am not so familiar trigonometry, but I have only two points to rotate in 2D:

                    *nx, ny
               .     -
          .           -
            


        

Answer 1

above accepted answer not work for me correctly, rotation are reversed , here is working function

/*
 CX @ Origin X  
 CY @ Origin Y
 X  @ Point X to be rotated
 Y  @ Point Y to be rotated  
 anticlock_wise @ to rotate point in clockwise direction or anticlockwise , default clockwise 
 return @ {x,y}  
*/
function rotate(cx, cy, x, y, angle,anticlock_wise = false) {
    if(angle == 0){
        return {x:parseFloat(x), y:parseFloat(y)};
    }if(anticlock_wise){
        var radians = (Math.PI / 180) * angle;
    }else{
        var radians = (Math.PI / -180) * angle;
    }
    var cos = Math.cos(radians);
    var sin = Math.sin(radians);
    var nx = (cos * (x - cx)) + (sin * (y - cy)) + cx;
    var ny = (cos * (y - cy)) - (sin * (x - cx)) + cy;
    return {x:nx, y:ny};
 }