E T3 cos 8, iz,&2\/cos 83 iZ2sind3\/E12 =elka(E12 sin& ins cos S 2 COSO 12 cosδ2cos6 sins, sins iZ, sin&, cos0,+iz, sins, cos& 3 E ikd/12 sind. coss +isIn, coso CoS 02 coS 8. H sins sins det(①T-elkd)=0