bai 4 mfile\LeThanhNguyen_bai4\bai 4.doc ...........\..................\bai 4.pdf ...........\..................\dat.mat ...........\..................\tinhieudat.m ...........\..................\vitri.fis ...........\..................\vitriballbeam3.mdl ...........\vao.mat ...........\vaomoi.mat ...........\vitriballbeam1.mdl ...........\LeThanhNguyen_bai4 bai 4 mfile