drawing a polygon with doubles?

hi all so i have a challenge to make a pentagon inscribed in a circle and i have to use the method of working out the cosines and sines as i have, but now when i come to draw my polygon it says error i cannot convert from double to int. am i missing something silly here or is this something that cannot happen and i need to find a different method to draw this with doubles?

double cosine1 = Math.Cos(2*Math.PI/5);
        double sine1 = Math.Sin(2 * Math.PI / 5);
        double cosine2 = Math.Cos(4*Math.PI/5);
        double sine2 = Math.Sin(4 * Math.PI / 5);
        double cosine3 = Math.Cos(6*Math.PI/5);
        double sine3 = Math.Sin(6 * Math.PI / 5);
        Point[] vertices = { new Point(cosine1, sine1), new Point(cosine2, sine2) };