For which purpose this fromula is used? - 0.5 * r^2 * sin A Share with your friends Share 1 Neelam Dubey answered this Dear student. This formula is used for finding area of segment where theta is angle of sector and r is radius. Regard -1 View Full Answer Sreehari S answered this this formula is used to find area of triangle when the theta value is less than 90 -1