How to divide a circle into three parts

Let there be a circle of radius R. it is Necessary to divide it into three equal parts with a compass. Open the compass to the radius of the circle. You can use this line, but you can put the needle of the compass in the center of the circle, and a leg to take to the circumference describing a circle. The range in any case will be useful later.Install the needle of the compass at an arbitrary position on the circumference describing a circle, and the pen to draw a small arc that intersects the outer contour of the circle. Then set the needle of the compass at the intersection point and again draw a arc with the same radius equal to the radius of the circle). Repeat these steps until the following point of intersection does not coincide with the first. You will receive six points on a circle, placed at equal intervals. It remains to choose three points in one line and connect them with the center of the circle and you will get a circle divided sodium.