format long s15 = sqrt((2-sqrt(3))/4) c15 = sqrt((2+sqrt(3))/4) s36 = sqrt((5-sqrt(5))/8) c36 = sqrt((3+sqrt(5))/8) s18 = sqrt(1/2-c36/2) c18 = sqrt(1/2+c36/2) s3 = s18 * c15 - c18 * s15 c3 = c18 * c15 + s18 * s15