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

According to Polar coordinate system artycle on Wikipedia:

x = r * cos(deg)
y = r * sin(deg)

• r (radius) is equal to distance between Rotation Centre and Rotated Point
• deg (degrees) is angle measured in degrees