||'''Book'''|| Linear Algebra ||
 ||'''Author'''|| Gilbert Strang ||
 ||'''Edition'''||  ||

/* code_begins */

{{{

F=matrix([[1,2,-2,0],[2,3,-4,1],[-1,-2,0,2],[0,2,5,3]])
print F
G=F.echelon_form() 
print G.det()
H=matrix([[2,-1,0,0],[-1,2,-1,0],[0,-1,2,-1],[0,0,-1,-2]])
print H
I=H.echelon_form() 
print I.det()
H.swap_rows(2,3); H
}}}

/* code_ends */

 * '''Solution by''': 
   * <C.Pratyusha>, <Student>, <SNIST>
   * <Reepu Kumari>, <student>, <SNIST>
   *<Renuka.Y>,<student>,<snist>