||'''Book'''|| Advanced Engineering Mathematics ||
 ||'''Author'''|| Erwin Kreyszig ||
 ||'''Edition'''|| 8th Edition ||

/* code_begins */

{{{
x=var('x')
y=function('y',x)
de=diff(y,x,2)+y-sec(x)
desolve(de,y)
}}}

/* code_ends */

 * '''Solution by''': 
   * umesh mishra, <student>, <army institute of technology pune>
   * nitish, <student>, <army institute of technolgy pune>