0977132人目の素数さん垢版 | 大砲2018/07/28(土) 16:24:52.44ID:EnyRsA6W ax = f, cx = g とおくと |a, b, c, d| |b, f, d, g| |c, d, ayy, byy| |d, g, byy, fyy| = {(af-bb)yy + (cg-dd)}^2 - (ag+cf-2bd)^2 yy = {(af-bb)yy +(ag+cf-2bd)y +(cg-dd)}{(af-bb)y^2 -(ag+cf-2bd)y +(cg-dd)},