Excerpt from Plane Cubics With a Given Quadrangle of Inflexions: A DissertationThen, as is known, the pencil of conics through the four points has a real common self-polar triangle with A, the intersection of the two given lines, as a vertex and bc, the polar line of A with respect to the given conic, as a side. It is further known that the remaining vertices B, C may be determined by a quadratic construction and hence, since every quadratic construction can be performed by means of the one given conic, the self-5 polar triangle may be constructed geometrically.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.