Ответ Автор - siestarjoki Теорема ЧевыAB1/B1C *CA1/A1B *BC1/C1A =11/2 *CA1/A1B *1/1 =1 <=> A1B/CA1 =1/2Теорема МенелаяBC1/C1A *AX/XA1 *A1C/CB =11/1 *AX/XA1 *2/3 =1 <=> AX/XA1 =3/2BA1/A1C *CX/XC1 *C1A/AB =11/2 *CX/XC1 *1/2 =1 <=> XC1/CX =1/4